ff7193776e
The only exception left are instances where aligning "=" helps to express symmetry between lines. See #443.
34 lines
1,016 B
JavaScript
34 lines
1,016 B
JavaScript
"use strict";
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let GrammarError = require("../../grammar-error");
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let asts = require("../asts");
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let visitor = require("../visitor");
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// Reports expressions that don't consume any input inside |*| or |+| in the
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// grammar, which prevents infinite loops in the generated parser.
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function reportInfiniteRepetition(ast) {
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let check = visitor.build({
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zero_or_more: function(node) {
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if (!asts.alwaysConsumesOnSuccess(ast, node.expression)) {
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throw new GrammarError(
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"Possible infinite loop when parsing (repetition used with an expression that may not consume any input).",
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node.location
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);
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}
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},
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one_or_more: function(node) {
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if (!asts.alwaysConsumesOnSuccess(ast, node.expression)) {
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throw new GrammarError(
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"Possible infinite loop when parsing (repetition used with an expression that may not consume any input).",
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node.location
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);
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}
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}
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});
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check(ast);
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}
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module.exports = reportInfiniteRepetition;
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