jhladmin/node_modules/@lezer/lr/dist/index.js

import { Parser, NodeSet, NodeType, DefaultBufferLength, NodeProp, Tree, IterMode } from '@lezer/common';

/// A parse stack. These are used internally by the parser to track
/// parsing progress. They also provide some properties and methods
/// that external code such as a tokenizer can use to get information
/// about the parse state.
class Stack {
    /// @internal
    constructor(
    /// The parse that this stack is part of @internal
    p, 
    /// Holds state, input pos, buffer index triplets for all but the
    /// top state @internal
    stack, 
    /// The current parse state @internal
    state, 
    // The position at which the next reduce should take place. This
    // can be less than `this.pos` when skipped expressions have been
    // added to the stack (which should be moved outside of the next
    // reduction)
    /// @internal
    reducePos, 
    /// The input position up to which this stack has parsed.
    pos, 
    /// The dynamic score of the stack, including dynamic precedence
    /// and error-recovery penalties
    /// @internal
    score, 
    // The output buffer. Holds (type, start, end, size) quads
    // representing nodes created by the parser, where `size` is
    // amount of buffer array entries covered by this node.
    /// @internal
    buffer, 
    // The base offset of the buffer. When stacks are split, the split
    // instance shared the buffer history with its parent up to
    // `bufferBase`, which is the absolute offset (including the
    // offset of previous splits) into the buffer at which this stack
    // starts writing.
    /// @internal
    bufferBase, 
    /// @internal
    curContext, 
    /// @internal
    lookAhead = 0, 
    // A parent stack from which this was split off, if any. This is
    // set up so that it always points to a stack that has some
    // additional buffer content, never to a stack with an equal
    // `bufferBase`.
    /// @internal
    parent) {
        this.p = p;
        this.stack = stack;
        this.state = state;
        this.reducePos = reducePos;
        this.pos = pos;
        this.score = score;
        this.buffer = buffer;
        this.bufferBase = bufferBase;
        this.curContext = curContext;
        this.lookAhead = lookAhead;
        this.parent = parent;
    }
    /// @internal
    toString() {
        return `[${this.stack.filter((_, i) => i % 3 == 0).concat(this.state)}]@${this.pos}${this.score ? "!" + this.score : ""}`;
    }
    // Start an empty stack
    /// @internal
    static start(p, state, pos = 0) {
        let cx = p.parser.context;
        return new Stack(p, [], state, pos, pos, 0, [], 0, cx ? new StackContext(cx, cx.start) : null, 0, null);
    }
    /// The stack's current [context](#lr.ContextTracker) value, if
    /// any. Its type will depend on the context tracker's type
    /// parameter, or it will be `null` if there is no context
    /// tracker.
    get context() { return this.curContext ? this.curContext.context : null; }
    // Push a state onto the stack, tracking its start position as well
    // as the buffer base at that point.
    /// @internal
    pushState(state, start) {
        this.stack.push(this.state, start, this.bufferBase + this.buffer.length);
        this.state = state;
    }
    // Apply a reduce action
    /// @internal
    reduce(action) {
        let depth = action >> 19 /* ReduceDepthShift */, type = action & 65535 /* ValueMask */;
        let { parser } = this.p;
        let dPrec = parser.dynamicPrecedence(type);
        if (dPrec)
            this.score += dPrec;
        if (depth == 0) {
            this.pushState(parser.getGoto(this.state, type, true), this.reducePos);
            // Zero-depth reductions are a special case—they add stuff to
            // the stack without popping anything off.
            if (type < parser.minRepeatTerm)
                this.storeNode(type, this.reducePos, this.reducePos, 4, true);
            this.reduceContext(type, this.reducePos);
            return;
        }
        // Find the base index into `this.stack`, content after which will
        // be dropped. Note that with `StayFlag` reductions we need to
        // consume two extra frames (the dummy parent node for the skipped
        // expression and the state that we'll be staying in, which should
        // be moved to `this.state`).
        let base = this.stack.length - ((depth - 1) * 3) - (action & 262144 /* StayFlag */ ? 6 : 0);
        let start = this.stack[base - 2];
        let bufferBase = this.stack[base - 1], count = this.bufferBase + this.buffer.length - bufferBase;
        // Store normal terms or `R -> R R` repeat reductions
        if (type < parser.minRepeatTerm || (action & 131072 /* RepeatFlag */)) {
            let pos = parser.stateFlag(this.state, 1 /* Skipped */) ? this.pos : this.reducePos;
            this.storeNode(type, start, pos, count + 4, true);
        }
        if (action & 262144 /* StayFlag */) {
            this.state = this.stack[base];
        }
        else {
            let baseStateID = this.stack[base - 3];
            this.state = parser.getGoto(baseStateID, type, true);
        }
        while (this.stack.length > base)
            this.stack.pop();
        this.reduceContext(type, start);
    }
    // Shift a value into the buffer
    /// @internal
    storeNode(term, start, end, size = 4, isReduce = false) {
        if (term == 0 /* Err */ &&
            (!this.stack.length || this.stack[this.stack.length - 1] < this.buffer.length + this.bufferBase)) {
            // Try to omit/merge adjacent error nodes
            let cur = this, top = this.buffer.length;
            if (top == 0 && cur.parent) {
                top = cur.bufferBase - cur.parent.bufferBase;
                cur = cur.parent;
            }
            if (top > 0 && cur.buffer[top - 4] == 0 /* Err */ && cur.buffer[top - 1] > -1) {
                if (start == end)
                    return;
                if (cur.buffer[top - 2] >= start) {
                    cur.buffer[top - 2] = end;
                    return;
                }
            }
        }
        if (!isReduce || this.pos == end) { // Simple case, just append
            this.buffer.push(term, start, end, size);
        }
        else { // There may be skipped nodes that have to be moved forward
            let index = this.buffer.length;
            if (index > 0 && this.buffer[index - 4] != 0 /* Err */)
                while (index > 0 && this.buffer[index - 2] > end) {
                    // Move this record forward
                    this.buffer[index] = this.buffer[index - 4];
                    this.buffer[index + 1] = this.buffer[index - 3];
                    this.buffer[index + 2] = this.buffer[index - 2];
                    this.buffer[index + 3] = this.buffer[index - 1];
                    index -= 4;
                    if (size > 4)
                        size -= 4;
                }
            this.buffer[index] = term;
            this.buffer[index + 1] = start;
            this.buffer[index + 2] = end;
            this.buffer[index + 3] = size;
        }
    }
    // Apply a shift action
    /// @internal
    shift(action, next, nextEnd) {
        let start = this.pos;
        if (action & 131072 /* GotoFlag */) {
            this.pushState(action & 65535 /* ValueMask */, this.pos);
        }
        else if ((action & 262144 /* StayFlag */) == 0) { // Regular shift
            let nextState = action, { parser } = this.p;
            if (nextEnd > this.pos || next <= parser.maxNode) {
                this.pos = nextEnd;
                if (!parser.stateFlag(nextState, 1 /* Skipped */))
                    this.reducePos = nextEnd;
            }
            this.pushState(nextState, start);
            this.shiftContext(next, start);
            if (next <= parser.maxNode)
                this.buffer.push(next, start, nextEnd, 4);
        }
        else { // Shift-and-stay, which means this is a skipped token
            this.pos = nextEnd;
            this.shiftContext(next, start);
            if (next <= this.p.parser.maxNode)
                this.buffer.push(next, start, nextEnd, 4);
        }
    }
    // Apply an action
    /// @internal
    apply(action, next, nextEnd) {
        if (action & 65536 /* ReduceFlag */)
            this.reduce(action);
        else
            this.shift(action, next, nextEnd);
    }
    // Add a prebuilt (reused) node into the buffer.
    /// @internal
    useNode(value, next) {
        let index = this.p.reused.length - 1;
        if (index < 0 || this.p.reused[index] != value) {
            this.p.reused.push(value);
            index++;
        }
        let start = this.pos;
        this.reducePos = this.pos = start + value.length;
        this.pushState(next, start);
        this.buffer.push(index, start, this.reducePos, -1 /* size == -1 means this is a reused value */);
        if (this.curContext)
            this.updateContext(this.curContext.tracker.reuse(this.curContext.context, value, this, this.p.stream.reset(this.pos - value.length)));
    }
    // Split the stack. Due to the buffer sharing and the fact
    // that `this.stack` tends to stay quite shallow, this isn't very
    // expensive.
    /// @internal
    split() {
        let parent = this;
        let off = parent.buffer.length;
        // Because the top of the buffer (after this.pos) may be mutated
        // to reorder reductions and skipped tokens, and shared buffers
        // should be immutable, this copies any outstanding skipped tokens
        // to the new buffer, and puts the base pointer before them.
        while (off > 0 && parent.buffer[off - 2] > parent.reducePos)
            off -= 4;
        let buffer = parent.buffer.slice(off), base = parent.bufferBase + off;
        // Make sure parent points to an actual parent with content, if there is such a parent.
        while (parent && base == parent.bufferBase)
            parent = parent.parent;
        return new Stack(this.p, this.stack.slice(), this.state, this.reducePos, this.pos, this.score, buffer, base, this.curContext, this.lookAhead, parent);
    }
    // Try to recover from an error by 'deleting' (ignoring) one token.
    /// @internal
    recoverByDelete(next, nextEnd) {
        let isNode = next <= this.p.parser.maxNode;
        if (isNode)
            this.storeNode(next, this.pos, nextEnd, 4);
        this.storeNode(0 /* Err */, this.pos, nextEnd, isNode ? 8 : 4);
        this.pos = this.reducePos = nextEnd;
        this.score -= 190 /* Delete */;
    }
    /// Check if the given term would be able to be shifted (optionally
    /// after some reductions) on this stack. This can be useful for
    /// external tokenizers that want to make sure they only provide a
    /// given token when it applies.
    canShift(term) {
        for (let sim = new SimulatedStack(this);;) {
            let action = this.p.parser.stateSlot(sim.state, 4 /* DefaultReduce */) || this.p.parser.hasAction(sim.state, term);
            if ((action & 65536 /* ReduceFlag */) == 0)
                return true;
            if (action == 0)
                return false;
            sim.reduce(action);
        }
    }
    // Apply up to Recover.MaxNext recovery actions that conceptually
    // inserts some missing token or rule.
    /// @internal
    recoverByInsert(next) {
        if (this.stack.length >= 300 /* MaxInsertStackDepth */)
            return [];
        let nextStates = this.p.parser.nextStates(this.state);
        if (nextStates.length > 4 /* MaxNext */ << 1 || this.stack.length >= 120 /* DampenInsertStackDepth */) {
            let best = [];
            for (let i = 0, s; i < nextStates.length; i += 2) {
                if ((s = nextStates[i + 1]) != this.state && this.p.parser.hasAction(s, next))
                    best.push(nextStates[i], s);
            }
            if (this.stack.length < 120 /* DampenInsertStackDepth */)
                for (let i = 0; best.length < 4 /* MaxNext */ << 1 && i < nextStates.length; i += 2) {
                    let s = nextStates[i + 1];
                    if (!best.some((v, i) => (i & 1) && v == s))
                        best.push(nextStates[i], s);
                }
            nextStates = best;
        }
        let result = [];
        for (let i = 0; i < nextStates.length && result.length < 4 /* MaxNext */; i += 2) {
            let s = nextStates[i + 1];
            if (s == this.state)
                continue;
            let stack = this.split();
            stack.pushState(s, this.pos);
            stack.storeNode(0 /* Err */, stack.pos, stack.pos, 4, true);
            stack.shiftContext(nextStates[i], this.pos);
            stack.score -= 200 /* Insert */;
            result.push(stack);
        }
        return result;
    }
    // Force a reduce, if possible. Return false if that can't
    // be done.
    /// @internal
    forceReduce() {
        let reduce = this.p.parser.stateSlot(this.state, 5 /* ForcedReduce */);
        if ((reduce & 65536 /* ReduceFlag */) == 0)
            return false;
        let { parser } = this.p;
        if (!parser.validAction(this.state, reduce)) {
            let depth = reduce >> 19 /* ReduceDepthShift */, term = reduce & 65535 /* ValueMask */;
            let target = this.stack.length - depth * 3;
            if (target < 0 || parser.getGoto(this.stack[target], term, false) < 0)
                return false;
            this.storeNode(0 /* Err */, this.reducePos, this.reducePos, 4, true);
            this.score -= 100 /* Reduce */;
        }
        this.reducePos = this.pos;
        this.reduce(reduce);
        return true;
    }
    /// @internal
    forceAll() {
        while (!this.p.parser.stateFlag(this.state, 2 /* Accepting */)) {
            if (!this.forceReduce()) {
                this.storeNode(0 /* Err */, this.pos, this.pos, 4, true);
                break;
            }
        }
        return this;
    }
    /// Check whether this state has no further actions (assumed to be a direct descendant of the
    /// top state, since any other states must be able to continue
    /// somehow). @internal
    get deadEnd() {
        if (this.stack.length != 3)
            return false;
        let { parser } = this.p;
        return parser.data[parser.stateSlot(this.state, 1 /* Actions */)] == 65535 /* End */ &&
            !parser.stateSlot(this.state, 4 /* DefaultReduce */);
    }
    /// Restart the stack (put it back in its start state). Only safe
    /// when this.stack.length == 3 (state is directly below the top
    /// state). @internal
    restart() {
        this.state = this.stack[0];
        this.stack.length = 0;
    }
    /// @internal
    sameState(other) {
        if (this.state != other.state || this.stack.length != other.stack.length)
            return false;
        for (let i = 0; i < this.stack.length; i += 3)
            if (this.stack[i] != other.stack[i])
                return false;
        return true;
    }
    /// Get the parser used by this stack.
    get parser() { return this.p.parser; }
    /// Test whether a given dialect (by numeric ID, as exported from
    /// the terms file) is enabled.
    dialectEnabled(dialectID) { return this.p.parser.dialect.flags[dialectID]; }
    shiftContext(term, start) {
        if (this.curContext)
            this.updateContext(this.curContext.tracker.shift(this.curContext.context, term, this, this.p.stream.reset(start)));
    }
    reduceContext(term, start) {
        if (this.curContext)
            this.updateContext(this.curContext.tracker.reduce(this.curContext.context, term, this, this.p.stream.reset(start)));
    }
    /// @internal
    emitContext() {
        let last = this.buffer.length - 1;
        if (last < 0 || this.buffer[last] != -3)
            this.buffer.push(this.curContext.hash, this.reducePos, this.reducePos, -3);
    }
    /// @internal
    emitLookAhead() {
        let last = this.buffer.length - 1;
        if (last < 0 || this.buffer[last] != -4)
            this.buffer.push(this.lookAhead, this.reducePos, this.reducePos, -4);
    }
    updateContext(context) {
        if (context != this.curContext.context) {
            let newCx = new StackContext(this.curContext.tracker, context);
            if (newCx.hash != this.curContext.hash)
                this.emitContext();
            this.curContext = newCx;
        }
    }
    /// @internal
    setLookAhead(lookAhead) {
        if (lookAhead > this.lookAhead) {
            this.emitLookAhead();
            this.lookAhead = lookAhead;
        }
    }
    /// @internal
    close() {
        if (this.curContext && this.curContext.tracker.strict)
            this.emitContext();
        if (this.lookAhead > 0)
            this.emitLookAhead();
    }
}
class StackContext {
    constructor(tracker, context) {
        this.tracker = tracker;
        this.context = context;
        this.hash = tracker.strict ? tracker.hash(context) : 0;
    }
}
var Recover;
(function (Recover) {
    Recover[Recover["Insert"] = 200] = "Insert";
    Recover[Recover["Delete"] = 190] = "Delete";
    Recover[Recover["Reduce"] = 100] = "Reduce";
    Recover[Recover["MaxNext"] = 4] = "MaxNext";
    Recover[Recover["MaxInsertStackDepth"] = 300] = "MaxInsertStackDepth";
    Recover[Recover["DampenInsertStackDepth"] = 120] = "DampenInsertStackDepth";
})(Recover || (Recover = {}));
// Used to cheaply run some reductions to scan ahead without mutating
// an entire stack
class SimulatedStack {
    constructor(start) {
        this.start = start;
        this.state = start.state;
        this.stack = start.stack;
        this.base = this.stack.length;
    }
    reduce(action) {
        let term = action & 65535 /* ValueMask */, depth = action >> 19 /* ReduceDepthShift */;
        if (depth == 0) {
            if (this.stack == this.start.stack)
                this.stack = this.stack.slice();
            this.stack.push(this.state, 0, 0);
            this.base += 3;
        }
        else {
            this.base -= (depth - 1) * 3;
        }
        let goto = this.start.p.parser.getGoto(this.stack[this.base - 3], term, true);
        this.state = goto;
    }
}
// This is given to `Tree.build` to build a buffer, and encapsulates
// the parent-stack-walking necessary to read the nodes.
class StackBufferCursor {
    constructor(stack, pos, index) {
        this.stack = stack;
        this.pos = pos;
        this.index = index;
        this.buffer = stack.buffer;
        if (this.index == 0)
            this.maybeNext();
    }
    static create(stack, pos = stack.bufferBase + stack.buffer.length) {
        return new StackBufferCursor(stack, pos, pos - stack.bufferBase);
    }
    maybeNext() {
        let next = this.stack.parent;
        if (next != null) {
            this.index = this.stack.bufferBase - next.bufferBase;
            this.stack = next;
            this.buffer = next.buffer;
        }
    }
    get id() { return this.buffer[this.index - 4]; }
    get start() { return this.buffer[this.index - 3]; }
    get end() { return this.buffer[this.index - 2]; }
    get size() { return this.buffer[this.index - 1]; }
    next() {
        this.index -= 4;
        this.pos -= 4;
        if (this.index == 0)
            this.maybeNext();
    }
    fork() {
        return new StackBufferCursor(this.stack, this.pos, this.index);
    }
}

class CachedToken {
    constructor() {
        this.start = -1;
        this.value = -1;
        this.end = -1;
        this.extended = -1;
        this.lookAhead = 0;
        this.mask = 0;
        this.context = 0;
    }
}
const nullToken = new CachedToken;
/// [Tokenizers](#lr.ExternalTokenizer) interact with the input
/// through this interface. It presents the input as a stream of
/// characters, tracking lookahead and hiding the complexity of
/// [ranges](#common.Parser.parse^ranges) from tokenizer code.
class InputStream {
    /// @internal
    constructor(
    /// @internal
    input, 
    /// @internal
    ranges) {
        this.input = input;
        this.ranges = ranges;
        /// @internal
        this.chunk = "";
        /// @internal
        this.chunkOff = 0;
        /// Backup chunk
        this.chunk2 = "";
        this.chunk2Pos = 0;
        /// The character code of the next code unit in the input, or -1
        /// when the stream is at the end of the input.
        this.next = -1;
        /// @internal
        this.token = nullToken;
        this.rangeIndex = 0;
        this.pos = this.chunkPos = ranges[0].from;
        this.range = ranges[0];
        this.end = ranges[ranges.length - 1].to;
        this.readNext();
    }
    /// @internal
    resolveOffset(offset, assoc) {
        let range = this.range, index = this.rangeIndex;
        let pos = this.pos + offset;
        while (pos < range.from) {
            if (!index)
                return null;
            let next = this.ranges[--index];
            pos -= range.from - next.to;
            range = next;
        }
        while (assoc < 0 ? pos > range.to : pos >= range.to) {
            if (index == this.ranges.length - 1)
                return null;
            let next = this.ranges[++index];
            pos += next.from - range.to;
            range = next;
        }
        return pos;
    }
    /// Look at a code unit near the stream position. `.peek(0)` equals
    /// `.next`, `.peek(-1)` gives you the previous character, and so
    /// on.
    ///
    /// Note that looking around during tokenizing creates dependencies
    /// on potentially far-away content, which may reduce the
    /// effectiveness incremental parsing—when looking forward—or even
    /// cause invalid reparses when looking backward more than 25 code
    /// units, since the library does not track lookbehind.
    peek(offset) {
        let idx = this.chunkOff + offset, pos, result;
        if (idx >= 0 && idx < this.chunk.length) {
            pos = this.pos + offset;
            result = this.chunk.charCodeAt(idx);
        }
        else {
            let resolved = this.resolveOffset(offset, 1);
            if (resolved == null)
                return -1;
            pos = resolved;
            if (pos >= this.chunk2Pos && pos < this.chunk2Pos + this.chunk2.length) {
                result = this.chunk2.charCodeAt(pos - this.chunk2Pos);
            }
            else {
                let i = this.rangeIndex, range = this.range;
                while (range.to <= pos)
                    range = this.ranges[++i];
                this.chunk2 = this.input.chunk(this.chunk2Pos = pos);
                if (pos + this.chunk2.length > range.to)
                    this.chunk2 = this.chunk2.slice(0, range.to - pos);
                result = this.chunk2.charCodeAt(0);
            }
        }
        if (pos >= this.token.lookAhead)
            this.token.lookAhead = pos + 1;
        return result;
    }
    /// Accept a token. By default, the end of the token is set to the
    /// current stream position, but you can pass an offset (relative to
    /// the stream position) to change that.
    acceptToken(token, endOffset = 0) {
        let end = endOffset ? this.resolveOffset(endOffset, -1) : this.pos;
        if (end == null || end < this.token.start)
            throw new RangeError("Token end out of bounds");
        this.token.value = token;
        this.token.end = end;
    }
    getChunk() {
        if (this.pos >= this.chunk2Pos && this.pos < this.chunk2Pos + this.chunk2.length) {
            let { chunk, chunkPos } = this;
            this.chunk = this.chunk2;
            this.chunkPos = this.chunk2Pos;
            this.chunk2 = chunk;
            this.chunk2Pos = chunkPos;
            this.chunkOff = this.pos - this.chunkPos;
        }
        else {
            this.chunk2 = this.chunk;
            this.chunk2Pos = this.chunkPos;
            let nextChunk = this.input.chunk(this.pos);
            let end = this.pos + nextChunk.length;
            this.chunk = end > this.range.to ? nextChunk.slice(0, this.range.to - this.pos) : nextChunk;
            this.chunkPos = this.pos;
            this.chunkOff = 0;
        }
    }
    readNext() {
        if (this.chunkOff >= this.chunk.length) {
            this.getChunk();
            if (this.chunkOff == this.chunk.length)
                return this.next = -1;
        }
        return this.next = this.chunk.charCodeAt(this.chunkOff);
    }
    /// Move the stream forward N (defaults to 1) code units. Returns
    /// the new value of [`next`](#lr.InputStream.next).
    advance(n = 1) {
        this.chunkOff += n;
        while (this.pos + n >= this.range.to) {
            if (this.rangeIndex == this.ranges.length - 1)
                return this.setDone();
            n -= this.range.to - this.pos;
            this.range = this.ranges[++this.rangeIndex];
            this.pos = this.range.from;
        }
        this.pos += n;
        if (this.pos >= this.token.lookAhead)
            this.token.lookAhead = this.pos + 1;
        return this.readNext();
    }
    setDone() {
        this.pos = this.chunkPos = this.end;
        this.range = this.ranges[this.rangeIndex = this.ranges.length - 1];
        this.chunk = "";
        return this.next = -1;
    }
    /// @internal
    reset(pos, token) {
        if (token) {
            this.token = token;
            token.start = pos;
            token.lookAhead = pos + 1;
            token.value = token.extended = -1;
        }
        else {
            this.token = nullToken;
        }
        if (this.pos != pos) {
            this.pos = pos;
            if (pos == this.end) {
                this.setDone();
                return this;
            }
            while (pos < this.range.from)
                this.range = this.ranges[--this.rangeIndex];
            while (pos >= this.range.to)
                this.range = this.ranges[++this.rangeIndex];
            if (pos >= this.chunkPos && pos < this.chunkPos + this.chunk.length) {
                this.chunkOff = pos - this.chunkPos;
            }
            else {
                this.chunk = "";
                this.chunkOff = 0;
            }
            this.readNext();
        }
        return this;
    }
    /// @internal
    read(from, to) {
        if (from >= this.chunkPos && to <= this.chunkPos + this.chunk.length)
            return this.chunk.slice(from - this.chunkPos, to - this.chunkPos);
        if (from >= this.chunk2Pos && to <= this.chunk2Pos + this.chunk2.length)
            return this.chunk2.slice(from - this.chunk2Pos, to - this.chunk2Pos);
        if (from >= this.range.from && to <= this.range.to)
            return this.input.read(from, to);
        let result = "";
        for (let r of this.ranges) {
            if (r.from >= to)
                break;
            if (r.to > from)
                result += this.input.read(Math.max(r.from, from), Math.min(r.to, to));
        }
        return result;
    }
}
/// @internal
class TokenGroup {
    constructor(data, id) {
        this.data = data;
        this.id = id;
    }
    token(input, stack) { readToken(this.data, input, stack, this.id); }
}
TokenGroup.prototype.contextual = TokenGroup.prototype.fallback = TokenGroup.prototype.extend = false;
/// `@external tokens` declarations in the grammar should resolve to
/// an instance of this class.
class ExternalTokenizer {
    /// Create a tokenizer. The first argument is the function that,
    /// given an input stream, scans for the types of tokens it
    /// recognizes at the stream's position, and calls
    /// [`acceptToken`](#lr.InputStream.acceptToken) when it finds
    /// one.
    constructor(
    /// @internal
    token, options = {}) {
        this.token = token;
        this.contextual = !!options.contextual;
        this.fallback = !!options.fallback;
        this.extend = !!options.extend;
    }
}
// Tokenizer data is stored a big uint16 array containing, for each
// state:
//
//  - A group bitmask, indicating what token groups are reachable from
//    this state, so that paths that can only lead to tokens not in
//    any of the current groups can be cut off early.
//
//  - The position of the end of the state's sequence of accepting
//    tokens
//
//  - The number of outgoing edges for the state
//
//  - The accepting tokens, as (token id, group mask) pairs
//
//  - The outgoing edges, as (start character, end character, state
//    index) triples, with end character being exclusive
//
// This function interprets that data, running through a stream as
// long as new states with the a matching group mask can be reached,
// and updating `input.token` when it matches a token.
function readToken(data, input, stack, group) {
    let state = 0, groupMask = 1 << group, { parser } = stack.p, { dialect } = parser;
    scan: for (;;) {
        if ((groupMask & data[state]) == 0)
            break;
        let accEnd = data[state + 1];
        // Check whether this state can lead to a token in the current group
        // Accept tokens in this state, possibly overwriting
        // lower-precedence / shorter tokens
        for (let i = state + 3; i < accEnd; i += 2)
            if ((data[i + 1] & groupMask) > 0) {
                let term = data[i];
                if (dialect.allows(term) &&
                    (input.token.value == -1 || input.token.value == term || parser.overrides(term, input.token.value))) {
                    input.acceptToken(term);
                    break;
                }
            }
        let next = input.next, low = 0, high = data[state + 2];
        // Special case for EOF
        if (input.next < 0 && high > low && data[accEnd + high * 3 - 3] == 65535 /* End */) {
            state = data[accEnd + high * 3 - 1];
            continue scan;
        }
        // Do a binary search on the state's edges
        for (; low < high;) {
            let mid = (low + high) >> 1;
            let index = accEnd + mid + (mid << 1);
            let from = data[index], to = data[index + 1];
            if (next < from)
                high = mid;
            else if (next >= to)
                low = mid + 1;
            else {
                state = data[index + 2];
                input.advance();
                continue scan;
            }
        }
        break;
    }
}

// See lezer-generator/src/encode.ts for comments about the encoding
// used here
function decodeArray(input, Type = Uint16Array) {
    if (typeof input != "string")
        return input;
    let array = null;
    for (let pos = 0, out = 0; pos < input.length;) {
        let value = 0;
        for (;;) {
            let next = input.charCodeAt(pos++), stop = false;
            if (next == 126 /* BigValCode */) {
                value = 65535 /* BigVal */;
                break;
            }
            if (next >= 92 /* Gap2 */)
                next--;
            if (next >= 34 /* Gap1 */)
                next--;
            let digit = next - 32 /* Start */;
            if (digit >= 46 /* Base */) {
                digit -= 46 /* Base */;
                stop = true;
            }
            value += digit;
            if (stop)
                break;
            value *= 46 /* Base */;
        }
        if (array)
            array[out++] = value;
        else
            array = new Type(value);
    }
    return array;
}

// Environment variable used to control console output
const verbose = typeof process != "undefined" && process.env && /\bparse\b/.test(process.env.LOG);
let stackIDs = null;
var Safety;
(function (Safety) {
    Safety[Safety["Margin"] = 25] = "Margin";
})(Safety || (Safety = {}));
function cutAt(tree, pos, side) {
    let cursor = tree.cursor(IterMode.IncludeAnonymous);
    cursor.moveTo(pos);
    for (;;) {
        if (!(side < 0 ? cursor.childBefore(pos) : cursor.childAfter(pos)))
            for (;;) {
                if ((side < 0 ? cursor.to < pos : cursor.from > pos) && !cursor.type.isError)
                    return side < 0 ? Math.max(0, Math.min(cursor.to - 1, pos - 25 /* Margin */))
                        : Math.min(tree.length, Math.max(cursor.from + 1, pos + 25 /* Margin */));
                if (side < 0 ? cursor.prevSibling() : cursor.nextSibling())
                    break;
                if (!cursor.parent())
                    return side < 0 ? 0 : tree.length;
            }
    }
}
class FragmentCursor {
    constructor(fragments, nodeSet) {
        this.fragments = fragments;
        this.nodeSet = nodeSet;
        this.i = 0;
        this.fragment = null;
        this.safeFrom = -1;
        this.safeTo = -1;
        this.trees = [];
        this.start = [];
        this.index = [];
        this.nextFragment();
    }
    nextFragment() {
        let fr = this.fragment = this.i == this.fragments.length ? null : this.fragments[this.i++];
        if (fr) {
            this.safeFrom = fr.openStart ? cutAt(fr.tree, fr.from + fr.offset, 1) - fr.offset : fr.from;
            this.safeTo = fr.openEnd ? cutAt(fr.tree, fr.to + fr.offset, -1) - fr.offset : fr.to;
            while (this.trees.length) {
                this.trees.pop();
                this.start.pop();
                this.index.pop();
            }
            this.trees.push(fr.tree);
            this.start.push(-fr.offset);
            this.index.push(0);
            this.nextStart = this.safeFrom;
        }
        else {
            this.nextStart = 1e9;
        }
    }
    // `pos` must be >= any previously given `pos` for this cursor
    nodeAt(pos) {
        if (pos < this.nextStart)
            return null;
        while (this.fragment && this.safeTo <= pos)
            this.nextFragment();
        if (!this.fragment)
            return null;
        for (;;) {
            let last = this.trees.length - 1;
            if (last < 0) { // End of tree
                this.nextFragment();
                return null;
            }
            let top = this.trees[last], index = this.index[last];
            if (index == top.children.length) {
                this.trees.pop();
                this.start.pop();
                this.index.pop();
                continue;
            }
            let next = top.children[index];
            let start = this.start[last] + top.positions[index];
            if (start > pos) {
                this.nextStart = start;
                return null;
            }
            if (next instanceof Tree) {
                if (start == pos) {
                    if (start < this.safeFrom)
                        return null;
                    let end = start + next.length;
                    if (end <= this.safeTo) {
                        let lookAhead = next.prop(NodeProp.lookAhead);
                        if (!lookAhead || end + lookAhead < this.fragment.to)
                            return next;
                    }
                }
                this.index[last]++;
                if (start + next.length >= Math.max(this.safeFrom, pos)) { // Enter this node
                    this.trees.push(next);
                    this.start.push(start);
                    this.index.push(0);
                }
            }
            else {
                this.index[last]++;
                this.nextStart = start + next.length;
            }
        }
    }
}
class TokenCache {
    constructor(parser, stream) {
        this.stream = stream;
        this.tokens = [];
        this.mainToken = null;
        this.actions = [];
        this.tokens = parser.tokenizers.map(_ => new CachedToken);
    }
    getActions(stack) {
        let actionIndex = 0;
        let main = null;
        let { parser } = stack.p, { tokenizers } = parser;
        let mask = parser.stateSlot(stack.state, 3 /* TokenizerMask */);
        let context = stack.curContext ? stack.curContext.hash : 0;
        let lookAhead = 0;
        for (let i = 0; i < tokenizers.length; i++) {
            if (((1 << i) & mask) == 0)
                continue;
            let tokenizer = tokenizers[i], token = this.tokens[i];
            if (main && !tokenizer.fallback)
                continue;
            if (tokenizer.contextual || token.start != stack.pos || token.mask != mask || token.context != context) {
                this.updateCachedToken(token, tokenizer, stack);
                token.mask = mask;
                token.context = context;
            }
            if (token.lookAhead > token.end + 25 /* Margin */)
                lookAhead = Math.max(token.lookAhead, lookAhead);
            if (token.value != 0 /* Err */) {
                let startIndex = actionIndex;
                if (token.extended > -1)
                    actionIndex = this.addActions(stack, token.extended, token.end, actionIndex);
                actionIndex = this.addActions(stack, token.value, token.end, actionIndex);
                if (!tokenizer.extend) {
                    main = token;
                    if (actionIndex > startIndex)
                        break;
                }
            }
        }
        while (this.actions.length > actionIndex)
            this.actions.pop();
        if (lookAhead)
            stack.setLookAhead(lookAhead);
        if (!main && stack.pos == this.stream.end) {
            main = new CachedToken;
            main.value = stack.p.parser.eofTerm;
            main.start = main.end = stack.pos;
            actionIndex = this.addActions(stack, main.value, main.end, actionIndex);
        }
        this.mainToken = main;
        return this.actions;
    }
    getMainToken(stack) {
        if (this.mainToken)
            return this.mainToken;
        let main = new CachedToken, { pos, p } = stack;
        main.start = pos;
        main.end = Math.min(pos + 1, p.stream.end);
        main.value = pos == p.stream.end ? p.parser.eofTerm : 0 /* Err */;
        return main;
    }
    updateCachedToken(token, tokenizer, stack) {
        tokenizer.token(this.stream.reset(stack.pos, token), stack);
        if (token.value > -1) {
            let { parser } = stack.p;
            for (let i = 0; i < parser.specialized.length; i++)
                if (parser.specialized[i] == token.value) {
                    let result = parser.specializers[i](this.stream.read(token.start, token.end), stack);
                    if (result >= 0 && stack.p.parser.dialect.allows(result >> 1)) {
                        if ((result & 1) == 0 /* Specialize */)
                            token.value = result >> 1;
                        else
                            token.extended = result >> 1;
                        break;
                    }
                }
        }
        else {
            token.value = 0 /* Err */;
            token.end = Math.min(stack.p.stream.end, stack.pos + 1);
        }
    }
    putAction(action, token, end, index) {
        // Don't add duplicate actions
        for (let i = 0; i < index; i += 3)
            if (this.actions[i] == action)
                return index;
        this.actions[index++] = action;
        this.actions[index++] = token;
        this.actions[index++] = end;
        return index;
    }
    addActions(stack, token, end, index) {
        let { state } = stack, { parser } = stack.p, { data } = parser;
        for (let set = 0; set < 2; set++) {
            for (let i = parser.stateSlot(state, set ? 2 /* Skip */ : 1 /* Actions */);; i += 3) {
                if (data[i] == 65535 /* End */) {
                    if (data[i + 1] == 1 /* Next */) {
                        i = pair(data, i + 2);
                    }
                    else {
                        if (index == 0 && data[i + 1] == 2 /* Other */)
                            index = this.putAction(pair(data, i + 2), token, end, index);
                        break;
                    }
                }
                if (data[i] == token)
                    index = this.putAction(pair(data, i + 1), token, end, index);
            }
        }
        return index;
    }
}
var Rec;
(function (Rec) {
    Rec[Rec["Distance"] = 5] = "Distance";
    Rec[Rec["MaxRemainingPerStep"] = 3] = "MaxRemainingPerStep";
    // When two stacks have been running independently long enough to
    // add this many elements to their buffers, prune one.
    Rec[Rec["MinBufferLengthPrune"] = 500] = "MinBufferLengthPrune";
    Rec[Rec["ForceReduceLimit"] = 10] = "ForceReduceLimit";
    // Once a stack reaches this depth (in .stack.length) force-reduce
    // it back to CutTo to avoid creating trees that overflow the stack
    // on recursive traversal.
    Rec[Rec["CutDepth"] = 15000] = "CutDepth";
    Rec[Rec["CutTo"] = 9000] = "CutTo";
})(Rec || (Rec = {}));
class Parse {
    constructor(parser, input, fragments, ranges) {
        this.parser = parser;
        this.input = input;
        this.ranges = ranges;
        this.recovering = 0;
        this.nextStackID = 0x2654; // ♔, ♕, ♖, ♗, ♘, ♙, ♠, ♡, ♢, ♣, ♤, ♥, ♦, ♧
        this.minStackPos = 0;
        this.reused = [];
        this.stoppedAt = null;
        this.stream = new InputStream(input, ranges);
        this.tokens = new TokenCache(parser, this.stream);
        this.topTerm = parser.top[1];
        let { from } = ranges[0];
        this.stacks = [Stack.start(this, parser.top[0], from)];
        this.fragments = fragments.length && this.stream.end - from > parser.bufferLength * 4
            ? new FragmentCursor(fragments, parser.nodeSet) : null;
    }
    get parsedPos() {
        return this.minStackPos;
    }
    // Move the parser forward. This will process all parse stacks at
    // `this.pos` and try to advance them to a further position. If no
    // stack for such a position is found, it'll start error-recovery.
    //
    // When the parse is finished, this will return a syntax tree. When
    // not, it returns `null`.
    advance() {
        let stacks = this.stacks, pos = this.minStackPos;
        // This will hold stacks beyond `pos`.
        let newStacks = this.stacks = [];
        let stopped, stoppedTokens;
        // Keep advancing any stacks at `pos` until they either move
        // forward or can't be advanced. Gather stacks that can't be
        // advanced further in `stopped`.
        for (let i = 0; i < stacks.length; i++) {
            let stack = stacks[i];
            for (;;) {
                this.tokens.mainToken = null;
                if (stack.pos > pos) {
                    newStacks.push(stack);
                }
                else if (this.advanceStack(stack, newStacks, stacks)) {
                    continue;
                }
                else {
                    if (!stopped) {
                        stopped = [];
                        stoppedTokens = [];
                    }
                    stopped.push(stack);
                    let tok = this.tokens.getMainToken(stack);
                    stoppedTokens.push(tok.value, tok.end);
                }
                break;
            }
        }
        if (!newStacks.length) {
            let finished = stopped && findFinished(stopped);
            if (finished)
                return this.stackToTree(finished);
            if (this.parser.strict) {
                if (verbose && stopped)
                    console.log("Stuck with token " + (this.tokens.mainToken ? this.parser.getName(this.tokens.mainToken.value) : "none"));
                throw new SyntaxError("No parse at " + pos);
            }
            if (!this.recovering)
                this.recovering = 5 /* Distance */;
        }
        if (this.recovering && stopped) {
            let finished = this.stoppedAt != null && stopped[0].pos > this.stoppedAt ? stopped[0]
                : this.runRecovery(stopped, stoppedTokens, newStacks);
            if (finished)
                return this.stackToTree(finished.forceAll());
        }
        if (this.recovering) {
            let maxRemaining = this.recovering == 1 ? 1 : this.recovering * 3 /* MaxRemainingPerStep */;
            if (newStacks.length > maxRemaining) {
                newStacks.sort((a, b) => b.score - a.score);
                while (newStacks.length > maxRemaining)
                    newStacks.pop();
            }
            if (newStacks.some(s => s.reducePos > pos))
                this.recovering--;
        }
        else if (newStacks.length > 1) {
            // Prune stacks that are in the same state, or that have been
            // running without splitting for a while, to avoid getting stuck
            // with multiple successful stacks running endlessly on.
            outer: for (let i = 0; i < newStacks.length - 1; i++) {
                let stack = newStacks[i];
                for (let j = i + 1; j < newStacks.length; j++) {
                    let other = newStacks[j];
                    if (stack.sameState(other) ||
                        stack.buffer.length > 500 /* MinBufferLengthPrune */ && other.buffer.length > 500 /* MinBufferLengthPrune */) {
                        if (((stack.score - other.score) || (stack.buffer.length - other.buffer.length)) > 0) {
                            newStacks.splice(j--, 1);
                        }
                        else {
                            newStacks.splice(i--, 1);
                            continue outer;
                        }
                    }
                }
            }
        }
        this.minStackPos = newStacks[0].pos;
        for (let i = 1; i < newStacks.length; i++)
            if (newStacks[i].pos < this.minStackPos)
                this.minStackPos = newStacks[i].pos;
        return null;
    }
    stopAt(pos) {
        if (this.stoppedAt != null && this.stoppedAt < pos)
            throw new RangeError("Can't move stoppedAt forward");
        this.stoppedAt = pos;
    }
    // Returns an updated version of the given stack, or null if the
    // stack can't advance normally. When `split` and `stacks` are
    // given, stacks split off by ambiguous operations will be pushed to
    // `split`, or added to `stacks` if they move `pos` forward.
    advanceStack(stack, stacks, split) {
        let start = stack.pos, { parser } = this;
        let base = verbose ? this.stackID(stack) + " -> " : "";
        if (this.stoppedAt != null && start > this.stoppedAt)
            return stack.forceReduce() ? stack : null;
        if (this.fragments) {
            let strictCx = stack.curContext && stack.curContext.tracker.strict, cxHash = strictCx ? stack.curContext.hash : 0;
            for (let cached = this.fragments.nodeAt(start); cached;) {
                let match = this.parser.nodeSet.types[cached.type.id] == cached.type ? parser.getGoto(stack.state, cached.type.id) : -1;
                if (match > -1 && cached.length && (!strictCx || (cached.prop(NodeProp.contextHash) || 0) == cxHash)) {
                    stack.useNode(cached, match);
                    if (verbose)
                        console.log(base + this.stackID(stack) + ` (via reuse of ${parser.getName(cached.type.id)})`);
                    return true;
                }
                if (!(cached instanceof Tree) || cached.children.length == 0 || cached.positions[0] > 0)
                    break;
                let inner = cached.children[0];
                if (inner instanceof Tree && cached.positions[0] == 0)
                    cached = inner;
                else
                    break;
            }
        }
        let defaultReduce = parser.stateSlot(stack.state, 4 /* DefaultReduce */);
        if (defaultReduce > 0) {
            stack.reduce(defaultReduce);
            if (verbose)
                console.log(base + this.stackID(stack) + ` (via always-reduce ${parser.getName(defaultReduce & 65535 /* ValueMask */)})`);
            return true;
        }
        if (stack.stack.length >= 15000 /* CutDepth */) {
            while (stack.stack.length > 9000 /* CutTo */ && stack.forceReduce()) { }
        }
        let actions = this.tokens.getActions(stack);
        for (let i = 0; i < actions.length;) {
            let action = actions[i++], term = actions[i++], end = actions[i++];
            let last = i == actions.length || !split;
            let localStack = last ? stack : stack.split();
            localStack.apply(action, term, end);
            if (verbose)
                console.log(base + this.stackID(localStack) + ` (via ${(action & 65536 /* ReduceFlag */) == 0 ? "shift"
                    : `reduce of ${parser.getName(action & 65535 /* ValueMask */)}`} for ${parser.getName(term)} @ ${start}${localStack == stack ? "" : ", split"})`);
            if (last)
                return true;
            else if (localStack.pos > start)
                stacks.push(localStack);
            else
                split.push(localStack);
        }
        return false;
    }
    // Advance a given stack forward as far as it will go. Returns the
    // (possibly updated) stack if it got stuck, or null if it moved
    // forward and was given to `pushStackDedup`.
    advanceFully(stack, newStacks) {
        let pos = stack.pos;
        for (;;) {
            if (!this.advanceStack(stack, null, null))
                return false;
            if (stack.pos > pos) {
                pushStackDedup(stack, newStacks);
                return true;
            }
        }
    }
    runRecovery(stacks, tokens, newStacks) {
        let finished = null, restarted = false;
        for (let i = 0; i < stacks.length; i++) {
            let stack = stacks[i], token = tokens[i << 1], tokenEnd = tokens[(i << 1) + 1];
            let base = verbose ? this.stackID(stack) + " -> " : "";
            if (stack.deadEnd) {
                if (restarted)
                    continue;
                restarted = true;
                stack.restart();
                if (verbose)
                    console.log(base + this.stackID(stack) + " (restarted)");
                let done = this.advanceFully(stack, newStacks);
                if (done)
                    continue;
            }
            let force = stack.split(), forceBase = base;
            for (let j = 0; force.forceReduce() && j < 10 /* ForceReduceLimit */; j++) {
                if (verbose)
                    console.log(forceBase + this.stackID(force) + " (via force-reduce)");
                let done = this.advanceFully(force, newStacks);
                if (done)
                    break;
                if (verbose)
                    forceBase = this.stackID(force) + " -> ";
            }
            for (let insert of stack.recoverByInsert(token)) {
                if (verbose)
                    console.log(base + this.stackID(insert) + " (via recover-insert)");
                this.advanceFully(insert, newStacks);
            }
            if (this.stream.end > stack.pos) {
                if (tokenEnd == stack.pos) {
                    tokenEnd++;
                    token = 0 /* Err */;
                }
                stack.recoverByDelete(token, tokenEnd);
                if (verbose)
                    console.log(base + this.stackID(stack) + ` (via recover-delete ${this.parser.getName(token)})`);
                pushStackDedup(stack, newStacks);
            }
            else if (!finished || finished.score < stack.score) {
                finished = stack;
            }
        }
        return finished;
    }
    // Convert the stack's buffer to a syntax tree.
    stackToTree(stack) {
        stack.close();
        return Tree.build({ buffer: StackBufferCursor.create(stack),
            nodeSet: this.parser.nodeSet,
            topID: this.topTerm,
            maxBufferLength: this.parser.bufferLength,
            reused: this.reused,
            start: this.ranges[0].from,
            length: stack.pos - this.ranges[0].from,
            minRepeatType: this.parser.minRepeatTerm });
    }
    stackID(stack) {
        let id = (stackIDs || (stackIDs = new WeakMap)).get(stack);
        if (!id)
            stackIDs.set(stack, id = String.fromCodePoint(this.nextStackID++));
        return id + stack;
    }
}
function pushStackDedup(stack, newStacks) {
    for (let i = 0; i < newStacks.length; i++) {
        let other = newStacks[i];
        if (other.pos == stack.pos && other.sameState(stack)) {
            if (newStacks[i].score < stack.score)
                newStacks[i] = stack;
            return;
        }
    }
    newStacks.push(stack);
}
class Dialect {
    constructor(source, flags, disabled) {
        this.source = source;
        this.flags = flags;
        this.disabled = disabled;
    }
    allows(term) { return !this.disabled || this.disabled[term] == 0; }
}
const id = x => x;
/// Context trackers are used to track stateful context (such as
/// indentation in the Python grammar, or parent elements in the XML
/// grammar) needed by external tokenizers. You declare them in a
/// grammar file as `@context exportName from "module"`.
///
/// Context values should be immutable, and can be updated (replaced)
/// on shift or reduce actions.
///
/// The export used in a `@context` declaration should be of this
/// type.
class ContextTracker {
    /// Define a context tracker.
    constructor(spec) {
        this.start = spec.start;
        this.shift = spec.shift || id;
        this.reduce = spec.reduce || id;
        this.reuse = spec.reuse || id;
        this.hash = spec.hash || (() => 0);
        this.strict = spec.strict !== false;
    }
}
/// Holds the parse tables for a given grammar, as generated by
/// `lezer-generator`, and provides [methods](#common.Parser) to parse
/// content with.
class LRParser extends Parser {
    /// @internal
    constructor(spec) {
        super();
        /// @internal
        this.wrappers = [];
        if (spec.version != 14 /* Version */)
            throw new RangeError(`Parser version (${spec.version}) doesn't match runtime version (${14 /* Version */})`);
        let nodeNames = spec.nodeNames.split(" ");
        this.minRepeatTerm = nodeNames.length;
        for (let i = 0; i < spec.repeatNodeCount; i++)
            nodeNames.push("");
        let topTerms = Object.keys(spec.topRules).map(r => spec.topRules[r][1]);
        let nodeProps = [];
        for (let i = 0; i < nodeNames.length; i++)
            nodeProps.push([]);
        function setProp(nodeID, prop, value) {
            nodeProps[nodeID].push([prop, prop.deserialize(String(value))]);
        }
        if (spec.nodeProps)
            for (let propSpec of spec.nodeProps) {
                let prop = propSpec[0];
                if (typeof prop == "string")
                    prop = NodeProp[prop];
                for (let i = 1; i < propSpec.length;) {
                    let next = propSpec[i++];
                    if (next >= 0) {
                        setProp(next, prop, propSpec[i++]);
                    }
                    else {
                        let value = propSpec[i + -next];
                        for (let j = -next; j > 0; j--)
                            setProp(propSpec[i++], prop, value);
                        i++;
                    }
                }
            }
        this.nodeSet = new NodeSet(nodeNames.map((name, i) => NodeType.define({
            name: i >= this.minRepeatTerm ? undefined : name,
            id: i,
            props: nodeProps[i],
            top: topTerms.indexOf(i) > -1,
            error: i == 0,
            skipped: spec.skippedNodes && spec.skippedNodes.indexOf(i) > -1
        })));
        if (spec.propSources)
            this.nodeSet = this.nodeSet.extend(...spec.propSources);
        this.strict = false;
        this.bufferLength = DefaultBufferLength;
        let tokenArray = decodeArray(spec.tokenData);
        this.context = spec.context;
        this.specialized = new Uint16Array(spec.specialized ? spec.specialized.length : 0);
        this.specializers = [];
        if (spec.specialized)
            for (let i = 0; i < spec.specialized.length; i++) {
                this.specialized[i] = spec.specialized[i].term;
                this.specializers[i] = spec.specialized[i].get;
            }
        this.states = decodeArray(spec.states, Uint32Array);
        this.data = decodeArray(spec.stateData);
        this.goto = decodeArray(spec.goto);
        this.maxTerm = spec.maxTerm;
        this.tokenizers = spec.tokenizers.map(value => typeof value == "number" ? new TokenGroup(tokenArray, value) : value);
        this.topRules = spec.topRules;
        this.dialects = spec.dialects || {};
        this.dynamicPrecedences = spec.dynamicPrecedences || null;
        this.tokenPrecTable = spec.tokenPrec;
        this.termNames = spec.termNames || null;
        this.maxNode = this.nodeSet.types.length - 1;
        this.dialect = this.parseDialect();
        this.top = this.topRules[Object.keys(this.topRules)[0]];
    }
    createParse(input, fragments, ranges) {
        let parse = new Parse(this, input, fragments, ranges);
        for (let w of this.wrappers)
            parse = w(parse, input, fragments, ranges);
        return parse;
    }
    /// Get a goto table entry @internal
    getGoto(state, term, loose = false) {
        let table = this.goto;
        if (term >= table[0])
            return -1;
        for (let pos = table[term + 1];;) {
            let groupTag = table[pos++], last = groupTag & 1;
            let target = table[pos++];
            if (last && loose)
                return target;
            for (let end = pos + (groupTag >> 1); pos < end; pos++)
                if (table[pos] == state)
                    return target;
            if (last)
                return -1;
        }
    }
    /// Check if this state has an action for a given terminal @internal
    hasAction(state, terminal) {
        let data = this.data;
        for (let set = 0; set < 2; set++) {
            for (let i = this.stateSlot(state, set ? 2 /* Skip */ : 1 /* Actions */), next;; i += 3) {
                if ((next = data[i]) == 65535 /* End */) {
                    if (data[i + 1] == 1 /* Next */)
                        next = data[i = pair(data, i + 2)];
                    else if (data[i + 1] == 2 /* Other */)
                        return pair(data, i + 2);
                    else
                        break;
                }
                if (next == terminal || next == 0 /* Err */)
                    return pair(data, i + 1);
            }
        }
        return 0;
    }
    /// @internal
    stateSlot(state, slot) {
        return this.states[(state * 6 /* Size */) + slot];
    }
    /// @internal
    stateFlag(state, flag) {
        return (this.stateSlot(state, 0 /* Flags */) & flag) > 0;
    }
    /// @internal
    validAction(state, action) {
        if (action == this.stateSlot(state, 4 /* DefaultReduce */))
            return true;
        for (let i = this.stateSlot(state, 1 /* Actions */);; i += 3) {
            if (this.data[i] == 65535 /* End */) {
                if (this.data[i + 1] == 1 /* Next */)
                    i = pair(this.data, i + 2);
                else
                    return false;
            }
            if (action == pair(this.data, i + 1))
                return true;
        }
    }
    /// Get the states that can follow this one through shift actions or
    /// goto jumps. @internal
    nextStates(state) {
        let result = [];
        for (let i = this.stateSlot(state, 1 /* Actions */);; i += 3) {
            if (this.data[i] == 65535 /* End */) {
                if (this.data[i + 1] == 1 /* Next */)
                    i = pair(this.data, i + 2);
                else
                    break;
            }
            if ((this.data[i + 2] & (65536 /* ReduceFlag */ >> 16)) == 0) {
                let value = this.data[i + 1];
                if (!result.some((v, i) => (i & 1) && v == value))
                    result.push(this.data[i], value);
            }
        }
        return result;
    }
    /// @internal
    overrides(token, prev) {
        let iPrev = findOffset(this.data, this.tokenPrecTable, prev);
        return iPrev < 0 || findOffset(this.data, this.tokenPrecTable, token) < iPrev;
    }
    /// Configure the parser. Returns a new parser instance that has the
    /// given settings modified. Settings not provided in `config` are
    /// kept from the original parser.
    configure(config) {
        // Hideous reflection-based kludge to make it easy to create a
        // slightly modified copy of a parser.
        let copy = Object.assign(Object.create(LRParser.prototype), this);
        if (config.props)
            copy.nodeSet = this.nodeSet.extend(...config.props);
        if (config.top) {
            let info = this.topRules[config.top];
            if (!info)
                throw new RangeError(`Invalid top rule name ${config.top}`);
            copy.top = info;
        }
        if (config.tokenizers)
            copy.tokenizers = this.tokenizers.map(t => {
                let found = config.tokenizers.find(r => r.from == t);
                return found ? found.to : t;
            });
        if (config.specializers)
            copy.specializers = this.specializers.map(s => {
                let found = config.specializers.find(r => r.from == s);
                return found ? found.to : s;
            });
        if (config.contextTracker)
            copy.context = config.contextTracker;
        if (config.dialect)
            copy.dialect = this.parseDialect(config.dialect);
        if (config.strict != null)
            copy.strict = config.strict;
        if (config.wrap)
            copy.wrappers = copy.wrappers.concat(config.wrap);
        if (config.bufferLength != null)
            copy.bufferLength = config.bufferLength;
        return copy;
    }
    /// Tells you whether any [parse wrappers](#lr.ParserConfig.wrap)
    /// are registered for this parser.
    hasWrappers() {
        return this.wrappers.length > 0;
    }
    /// Returns the name associated with a given term. This will only
    /// work for all terms when the parser was generated with the
    /// `--names` option. By default, only the names of tagged terms are
    /// stored.
    getName(term) {
        return this.termNames ? this.termNames[term] : String(term <= this.maxNode && this.nodeSet.types[term].name || term);
    }
    /// The eof term id is always allocated directly after the node
    /// types. @internal
    get eofTerm() { return this.maxNode + 1; }
    /// The type of top node produced by the parser.
    get topNode() { return this.nodeSet.types[this.top[1]]; }
    /// @internal
    dynamicPrecedence(term) {
        let prec = this.dynamicPrecedences;
        return prec == null ? 0 : prec[term] || 0;
    }
    /// @internal
    parseDialect(dialect) {
        let values = Object.keys(this.dialects), flags = values.map(() => false);
        if (dialect)
            for (let part of dialect.split(" ")) {
                let id = values.indexOf(part);
                if (id >= 0)
                    flags[id] = true;
            }
        let disabled = null;
        for (let i = 0; i < values.length; i++)
            if (!flags[i]) {
                for (let j = this.dialects[values[i]], id; (id = this.data[j++]) != 65535 /* End */;)
                    (disabled || (disabled = new Uint8Array(this.maxTerm + 1)))[id] = 1;
            }
        return new Dialect(dialect, flags, disabled);
    }
    /// (used by the output of the parser generator) @internal
    static deserialize(spec) {
        return new LRParser(spec);
    }
}
function pair(data, off) { return data[off] | (data[off + 1] << 16); }
function findOffset(data, start, term) {
    for (let i = start, next; (next = data[i]) != 65535 /* End */; i++)
        if (next == term)
            return i - start;
    return -1;
}
function findFinished(stacks) {
    let best = null;
    for (let stack of stacks) {
        let stopped = stack.p.stoppedAt;
        if ((stack.pos == stack.p.stream.end || stopped != null && stack.pos > stopped) &&
            stack.p.parser.stateFlag(stack.state, 2 /* Accepting */) &&
            (!best || best.score < stack.score))
            best = stack;
    }
    return best;
}

export { ContextTracker, ExternalTokenizer, InputStream, LRParser, Stack };