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Code Issues Projects Releases Wiki Activity

Tokenizer now correctly recognizes Outdents

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This commit is contained in:
Patrick Demian 2020-10-27 13:24:23 -04:00
parent 5e9c185923
commit 44838b8a43
7 changed files with 313 additions and 9451 deletions
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9155
docs/bundle.min.js vendored
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File diff suppressed because one or more lines are too long

2
src/parser.ts
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@ -1,7 +1,7 @@
/*! Copyright (c) 2020 Patrick Demian; Licensed under MIT */
import { CstParser } from "chevrotain";
import * as T from "./tokenizer";
import * as T from "./tokens";
export class Human2RegexParser extends CstParser {
constructor() {

15
src/script.ts
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@ -2,8 +2,7 @@
import "./style.css";
import { Human2RegexLexer } from './tokenizer';
import { Human2RegexParser } from './parser';
import { Human2RegexLexer } from "./tokenizer";
/*
$(function() {
@ -11,7 +10,9 @@ $(function() {
});
*/
const result = Human2RegexLexer.tokenize(`
const lexer = new Human2RegexLexer();
const result = lexer.tokenize(`
// H2R supports // # and /**/ as comments
// A group is only captured if given a name.
// You can use "and", "or", "not" to specify "[]" regex
@ -52,6 +53,14 @@ create an optional group
match 0+ any thing
`);
//let str = "";
//for(const r of result.tokens) {
// str += r.tokenType === Newline ? "\n" : r.image + " ";
//}
//console.log(str);
for(const r of result.tokens) {
console.log(r);
}

411
src/tokenizer.ts
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@ -1,179 +1,8 @@
/*! Copyright (c) 2020 Patrick Demian; Licensed under MIT */
import { createToken, Lexer, IToken, createTokenInstance, ILexingResult } from "chevrotain";
export const Zero = createToken({name: "Zero", pattern: /zero/i });
export const One = createToken({name: "One", pattern: /one/i });
export const Two = createToken({name: "Two", pattern: /two/i });
export const Three = createToken({name: "Three", pattern: /three/i });
export const Four = createToken({name: "Four", pattern: /four/i });
export const Five = createToken({name: "Five", pattern: /five/i });
export const Six = createToken({name: "Six", pattern: /six/i });
export const Seven = createToken({name: "Seven", pattern: /seven/i });
export const Eight = createToken({name: "Eight", pattern: /eight/i });
export const Nine = createToken({name: "Nine", pattern: /nine/i });
export const Ten = createToken({name: "Ten", pattern: /ten/i });
export const Optional = createToken({name: "Optional", pattern: /optional(ly)?/i });
export const Match = createToken({name: "Match", pattern: /match(es)?/i });
export const Then = createToken({name: "Then", pattern: /then/i });
export const Anything = createToken({name: "Anything", pattern: /(any thing|any|anything)(s)?/i});
export const Of = createToken({name: "Of", pattern: /of/i});
export const Or = createToken({name: "Or", pattern: /or/i});
export const And = createToken({name: "And", pattern: /and|,/i});
export const Word = createToken({name: "Word Specifier", pattern: /word(s)?/i});
export const Digit = createToken({name: "Digit Specifier", pattern: /digit(s)?/i});
export const Character = createToken({name: "Character Specifier", pattern: /character(s)?/i});
export const Whitespace = createToken({name: "Whitespace Specifier", pattern: /(white space|whitespace)(s)?/i});
export const Number = createToken({name: "NumberSpecifier", pattern: /number(s)?/i});
export const As = createToken({name: "As", pattern: /as/i});
export const If = createToken({name: "If", pattern: /if/i});
export const Start = createToken({name: "Start", pattern: /start(s)?/i});
export const With = createToken({name: "With", pattern: /with/i});
export const Ends = createToken({name: "Ends", pattern: /end(s)?/i});
export const Otherwise = createToken({name: "Otherwise", pattern: /(other wise|otherwise)/i});
export const Else = createToken({name: "Else", pattern: /else/i});
export const Unless = createToken({name: "Unless", pattern: /unless/i});
export const While = createToken({name: "While", pattern: /while/i});
export const More = createToken({name: "More", pattern: /more/i});
export const Using = createToken({name: "Using", pattern: /using/i});
export const Global = createToken({name: "Global", pattern: /global/i});
export const Multiline = createToken({name: "Multiline", pattern: /(multi line|multiline)/i});
export const Exact = createToken({name: "Exact", pattern: /exact/i});
export const Matching = createToken({name: "Matching", pattern: /matching/i});
export const Nothing = createToken({name: "Nothing", pattern: /nothing/i});
export const Not = createToken({name: "Not", pattern: /not/i }); //, longer_alt: Nothing});
export const Between = createToken({name: "Between", pattern: /between/i});
export const Tab = createToken({name: "Tab", pattern: /tab/i});
export const Linefeed = createToken({name: "Linefeed", pattern: /(line feed|linefeed)/i});
export const Group = createToken({name: "Group", pattern: /group/i});
export const By = createToken({name: "By", pattern: /by/i});
export const A = createToken({name: "A", pattern: /a(n)?/i }); //, longer_alt: Anything});
export const The = createToken({name: "The", pattern: /the/i }); //, longer_alt: Then});
export const Exactly = createToken({name: "Exactly", pattern: /exact(ly)?/i});
export const Inclusive = createToken({name: "Inclusive", pattern: /inclusive(ly)?/i});
export const Exclusive = createToken({name: "Exclusive", pattern: /exclusive(ly)?/i});
export const From = createToken({name: "From", pattern: /from/i});
export const To = createToken({name: "To", pattern: /(to|\-|\.\.|\.\.\.)/i});
export const Create = createToken({name: "Create", pattern: /create(s)?/i});
export const Called = createToken({name: "Called", pattern: /called/i});
export const Repeat = createToken({name: "Repeat", pattern: /repeat(s|ing)?/i});
export const Newline = createToken({name: "Newline", pattern: /(new line|newline)/i});
export const None = createToken({name: "None", pattern: /none/i});
export const Neither = createToken({name: "Neither", pattern: /neither/i});
export const CarriageReturn = createToken({name: "Carriage Return", pattern: /carriage return/i});
export const CaseInsensitive = createToken({name: "Case Insensitive", pattern: /case insensitive/i});
export const CaseSensitive = createToken({name: "Case Sensitive", pattern: /case sensitive/i});
export const OrMore = createToken({name: "Or More", pattern: /\+/ });
export const LBracket = createToken({name: "Left Bracket", pattern: /\(/ });
export const RBracket = createToken({name: "Right Bracket", pattern: /\)/ });
export const EndOfLine = createToken({name: "EOL", pattern: /\n/, group: "nl" });
export const WhiteSpace = createToken({name: "Whitespace", pattern: /\s+/, group: Lexer.SKIPPED });
export const SingleLineComment = createToken({name: "Single-Line Comment", pattern: /(#|\/\/).*/, group: Lexer.SKIPPED });
export const MultilineComment = createToken({name: "Multi-Line Comment", pattern: /\/\*(.*)\*\//, line_breaks: true, group: Lexer.SKIPPED });
export const Identifier = createToken({name: "Identifier", pattern: /[a-z]\w*/i });
export const NumberLiteral = createToken({name: "Number Literal", pattern: /-?(0|[1-9]\d*)(\.\d+)?([eE][+-]?\d+)?/ });
export const StringLiteral = createToken({name: "String Literal", pattern: /"(?:[^\\"]|\\(?:[bfnrtv"\\/]|u[0-9a-f]{4}|U[0-9a-f]{8}))*"/i });
enum IndentBaseType {
Indent,
Outdent
}
export const Indent = createToken({
name: "Indent",
start_chars_hint: [ "\t", " " ],
pattern: (text, offset, matchedTokens, groups) => Human2RegexLexer.matchIndentBase(text, offset, matchedTokens, groups, IndentBaseType.Indent),
// custom token patterns should explicitly specify the line_breaks option
line_breaks: false
});
export const Outdent = createToken({
name: "Outdent",
start_chars_hint: [ "\t", " " ],
pattern: (text, offset, matchedTokens, groups) => Human2RegexLexer.matchIndentBase(text, offset, matchedTokens, groups, IndentBaseType.Outdent),
// custom token patterns should explicitly specify the line_breaks option
line_breaks: false
});
export const AllTokens = [
Zero,
One,
Two,
Three,
Four,
Five,
Six,
Seven,
Eight,
Nine,
Ten,
Optional,
Matching,
Match,
Then,
Anything,
Of,
Or,
And,
Word,
Digit,
Character,
Whitespace,
Number,
As,
If,
Start,
With,
Ends,
Otherwise,
Else,
Unless,
While,
More,
Using,
Global,
Multiline,
Exact,
Nothing,
Not,
Between,
Tab,
Linefeed,
Group,
By,
A,
The,
Exactly,
Inclusive,
Exclusive,
From,
Create,
Called,
Repeat,
Newline,
None,
Neither,
CarriageReturn,
CaseInsensitive,
CaseSensitive,
OrMore,
To,
EndOfLine,
Indent,
Outdent,
WhiteSpace,
SingleLineComment,
MultilineComment,
Identifier,
NumberLiteral,
StringLiteral,
];
const H2RLexer = new Lexer(AllTokens, { ensureOptimizations: true });
import { Lexer, IToken, createTokenInstance, ILexingResult } from "chevrotain";
import { last, findLastIndex } from "./utilities";
import { Indent, Outdent, EndOfLine, AllTokens } from "./tokens";
export enum IndentType {
Tabs,
@ -188,118 +17,21 @@ export class Human2RegexLexerOptions {
}
export class Human2RegexLexer {
//Taken and adapted from https://github.com/SAP/chevrotain/blob/master/examples/lexer/python_indentation/python_indentation.js
private static already_init = false;
// State required for matching the indentations
private static options = new Human2RegexLexerOptions();
private static indentStack = [ 0 ];
private static wsRegExp: RegExp;
private static spacesPerTab = " ";
private lexer : Lexer;
private static findLastIndex<T>(array: T[], predicate: (x: T) => boolean) : number {
for (let index = array.length; index >= 0; index--) {
if (predicate(array[index])) {
return index;
}
}
return -1;
constructor(private options: Human2RegexLexerOptions = new Human2RegexLexerOptions()) {
if (Human2RegexLexer.already_init) {
throw new Error("Only 1 instance of Human2RegexLexer allowed");
}
/**
* This custom Token matcher uses Lexer context ("matchedTokens" and "groups" arguments)
* combined with state via closure ("indentStack" and "lastTextMatched") to match indentation.
*/
public static matchIndentBase(text: string, offset: number, matchedTokens: IToken[], groups: {[groupName: string]: IToken[]}, type: IndentBaseType) : RegExpExecArray | null {
const noTokensMatchedYet = !matchedTokens.length;
const newLines = groups.nl;
const noNewLinesMatchedYet = !newLines.length;
const isFirstLine = noTokensMatchedYet && noNewLinesMatchedYet;
const isStartOfLine =
// only newlines matched so far
(noTokensMatchedYet && !noNewLinesMatchedYet) ||
// Both newlines and other Tokens have been matched AND the offset is just after the last newline
(!noTokensMatchedYet &&
!noNewLinesMatchedYet &&
offset === newLines[newLines.length-1].startOffset + 1);
Human2RegexLexer.already_init = true;
// indentation can only be matched at the start of a line.
if (isFirstLine || isStartOfLine) {
let currIndentLevel: number = -1;
let indent_regex: RegExp | null = null;
Human2RegexLexer.wsRegExp.lastIndex = offset;
const match = Human2RegexLexer.wsRegExp.exec(text);
// possible non-empty indentation
if (match !== null) {
currIndentLevel = match[0].length;
//if (this.options.type === IndentType.Tabs) {
// currIndentLevel = match[0].length;
//}
//else {
// currIndentLevel = match[0].replace(Human2RegexLexer.spacesPerTab, "\t").length;
//}
}
// "empty" indentation means indentLevel of 0.
else {
currIndentLevel = 0;
}
const prevIndentLevel = this.indentStack[this.indentStack.length-1];
// deeper indentation
if (currIndentLevel > prevIndentLevel && type === IndentBaseType.Indent) {
this.indentStack.push(currIndentLevel);
return match;
}
// shallower indentation
else if (currIndentLevel < prevIndentLevel && type === IndentBaseType.Outdent) {
const matchIndentIndex = this.findLastIndex(this.indentStack, (stackIndentDepth) => stackIndentDepth === currIndentLevel);
// any outdent must match some previous indentation level.
if (matchIndentIndex === -1) {
throw Error(`invalid outdent at offset: ${offset}`);
}
const numberOfDedents = this.indentStack.length - matchIndentIndex - 1;
// This is a little tricky
// 1. If there is no match (0 level indent) than this custom token
// matcher would return "null" and so we need to add all the required outdents ourselves.
// 2. If there was match (> 0 level indent) than we need to add minus one number of outsents
// because the lexer would create one due to returning a none null result.
const iStart = match !== null ? 1 : 0;
for (let i = iStart; i < numberOfDedents; i++) {
this.indentStack.pop();
matchedTokens.push(createTokenInstance(Outdent, "", NaN, NaN, NaN, NaN, NaN, NaN));
}
// even though we are adding fewer outdents directly we still need to update the indent stack fully.
if (iStart === 1) {
this.indentStack.pop();
}
return match;
}
else {
// same indent, this should be lexed as simple whitespace and ignored
return null;
}
}
else {
// indentation cannot be matched under other circumstances
return null;
}
}
public static tokenize(text: string, options: Human2RegexLexerOptions | null = null) : ILexingResult{
// have to reset the indent stack between processing of different text inputs
Human2RegexLexer.indentStack = [ 0 ];
if (options !== null) {
Human2RegexLexer.options = this.options;
}
/*
if (this.options.type === IndentType.Tabs) {
Human2RegexLexer.wsRegExp = /\t/y;
indent_regex = /\t/y;
}
else {
let reg = ` {${this.options.spaces_per_tab}}`;
@ -308,20 +40,117 @@ export class Human2RegexLexer {
reg += "|\\t";
}
Human2RegexLexer.wsRegExp = new RegExp(reg, "y");
Human2RegexLexer.spacesPerTab = Array(this.options.spaces_per_tab+1).join(" ");
}*/
Human2RegexLexer.wsRegExp = / +/y;
const lexResult = H2RLexer.tokenize(text);
//add remaining Outdents
while (Human2RegexLexer.indentStack.length > 1) {
lexResult.tokens.push(createTokenInstance(Outdent, "", NaN, NaN, NaN, NaN, NaN, NaN));
Human2RegexLexer.indentStack.pop();
indent_regex = new RegExp(reg, "y");
}
Indent.PATTERN = indent_regex;
this.lexer = new Lexer(AllTokens, { ensureOptimizations: true });
}
public tokenize(text: string) : ILexingResult {
const lexResult = this.lexer.tokenize(text);
if (lexResult.tokens.length == 0) {
return lexResult;
}
// create Outdents
const tokens: IToken[] = [];
const indentStack = [ 0 ];
let currIndentLevel = 0;
let startOfLine = true;
let hadIndents = false;
for (let i = 0; i < lexResult.tokens.length; i++) {
if (lexResult.tokens[i].tokenType === EndOfLine) {
startOfLine = true;
tokens.push(lexResult.tokens[i]);
}
else if (lexResult.tokens[i].tokenType === Indent) {
hadIndents = true;
currIndentLevel = 1;
const start_token = lexResult.tokens[i];
let length = lexResult.tokens[i].image.length;
while (lexResult.tokens[i+1].tokenType === Indent) {
currIndentLevel++;
i++;
length += lexResult.tokens[i].image.length;
}
if (!startOfLine || (currIndentLevel > last(indentStack) + 1)) {
lexResult.errors.push({
offset: start_token.startOffset,
line: start_token.startLine ?? NaN,
column: start_token.startColumn ?? NaN,
length: length,
message: "Unexpected indentation found"
});
}
else if (currIndentLevel > last(indentStack)) {
indentStack.push(currIndentLevel);
tokens.push(start_token);
}
else if (currIndentLevel < last(indentStack)) {
const index = findLastIndex(indentStack, currIndentLevel);
if (index < 0) {
lexResult.errors.push({
offset: start_token.startOffset,
line: start_token.startLine ?? NaN,
column: start_token.startColumn ?? NaN,
length: length,
message: "Unexpected indentation found"
});
}
else {
const numberOfDedents = indentStack.length - index - 1;
for(let i = 0; i < numberOfDedents; i++) {
indentStack.pop();
tokens.push(createTokenInstance(Outdent, "", start_token.startOffset, start_token.startOffset + length, start_token.startLine ?? NaN, start_token.endLine ?? NaN, start_token.startColumn ?? NaN, (start_token.startColumn ?? NaN) + length));
}
}
}
else {
// same indent level: don't care
}
}
else {
if(startOfLine && !hadIndents) {
const tok = lexResult.tokens[i];
while (indentStack.length > 1) {
indentStack.pop();
tokens.push(createTokenInstance(Outdent, "", tok.startOffset, tok.startOffset, tok.startLine ?? NaN, NaN, tok.startColumn ?? NaN, NaN));
}
}
startOfLine = false;
hadIndents = false;
tokens.push(lexResult.tokens[i]);
}
}
const tok = last(tokens);
// Do we have an EOL marker at the end?
if(tok.tokenType !== EndOfLine) {
tokens.push(createTokenInstance(EndOfLine, "\n", tok.endOffset ?? NaN, tok.endOffset ?? NaN, tok.startLine ?? NaN, NaN, tok.startColumn ?? NaN, NaN));
}
//add remaining Outdents
while (indentStack.length > 1) {
indentStack.pop();
tokens.push(createTokenInstance(Outdent, "", tok.endOffset ?? NaN, tok.endOffset ?? NaN, tok.startLine ?? NaN, NaN, tok.startColumn ?? NaN, NaN));
}
lexResult.tokens = tokens;
return lexResult;
}
}

154
src/tokens.ts Normal file
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@ -0,0 +1,154 @@
import { createToken, Lexer } from "chevrotain";
export const Zero = createToken({name: "Zero", pattern: /zero/i });
export const One = createToken({name: "One", pattern: /one/i });
export const Two = createToken({name: "Two", pattern: /two/i });
export const Three = createToken({name: "Three", pattern: /three/i });
export const Four = createToken({name: "Four", pattern: /four/i });
export const Five = createToken({name: "Five", pattern: /five/i });
export const Six = createToken({name: "Six", pattern: /six/i });
export const Seven = createToken({name: "Seven", pattern: /seven/i });
export const Eight = createToken({name: "Eight", pattern: /eight/i });
export const Nine = createToken({name: "Nine", pattern: /nine/i });
export const Ten = createToken({name: "Ten", pattern: /ten/i });
export const Optional = createToken({name: "Optional", pattern: /optional(ly)?/i });
export const Match = createToken({name: "Match", pattern: /match(es)?/i });
export const Then = createToken({name: "Then", pattern: /then/i });
export const Anything = createToken({name: "Anything", pattern: /(any thing|any|anything)(s)?/i});
export const Of = createToken({name: "Of", pattern: /of/i});
export const Or = createToken({name: "Or", pattern: /or/i});
export const And = createToken({name: "And", pattern: /and|,/i});
export const Word = createToken({name: "Word Specifier", pattern: /word(s)?/i});
export const Digit = createToken({name: "Digit Specifier", pattern: /digit(s)?/i});
export const Character = createToken({name: "Character Specifier", pattern: /character(s)?/i});
export const Whitespace = createToken({name: "Whitespace Specifier", pattern: /(white space|whitespace)(s)?/i});
export const Number = createToken({name: "NumberSpecifier", pattern: /number(s)?/i});
export const As = createToken({name: "As", pattern: /as/i});
export const If = createToken({name: "If", pattern: /if/i});
export const Start = createToken({name: "Start", pattern: /start(s)?/i});
export const With = createToken({name: "With", pattern: /with/i});
export const Ends = createToken({name: "Ends", pattern: /end(s)?/i});
export const Otherwise = createToken({name: "Otherwise", pattern: /(other wise|otherwise)/i});
export const Else = createToken({name: "Else", pattern: /else/i});
export const Unless = createToken({name: "Unless", pattern: /unless/i});
export const While = createToken({name: "While", pattern: /while/i});
export const More = createToken({name: "More", pattern: /more/i});
export const Using = createToken({name: "Using", pattern: /using/i});
export const Global = createToken({name: "Global", pattern: /global/i});
export const Multiline = createToken({name: "Multiline", pattern: /(multi line|multiline)/i});
export const Exact = createToken({name: "Exact", pattern: /exact/i});
export const Matching = createToken({name: "Matching", pattern: /matching/i});
export const Nothing = createToken({name: "Nothing", pattern: /nothing/i});
export const Not = createToken({name: "Not", pattern: /not/i }); //, longer_alt: Nothing});
export const Between = createToken({name: "Between", pattern: /between/i});
export const Tab = createToken({name: "Tab", pattern: /tab/i});
export const Linefeed = createToken({name: "Linefeed", pattern: /(line feed|linefeed)/i});
export const Group = createToken({name: "Group", pattern: /group/i});
export const By = createToken({name: "By", pattern: /by/i});
export const A = createToken({name: "A", pattern: /a(n)?/i }); //, longer_alt: Anything});
export const The = createToken({name: "The", pattern: /the/i }); //, longer_alt: Then});
export const Exactly = createToken({name: "Exactly", pattern: /exact(ly)?/i});
export const Inclusive = createToken({name: "Inclusive", pattern: /inclusive(ly)?/i});
export const Exclusive = createToken({name: "Exclusive", pattern: /exclusive(ly)?/i});
export const From = createToken({name: "From", pattern: /from/i});
export const To = createToken({name: "To", pattern: /(to|\-|\.\.|\.\.\.)/i});
export const Create = createToken({name: "Create", pattern: /create(s)?/i});
export const Called = createToken({name: "Called", pattern: /called/i});
export const Repeat = createToken({name: "Repeat", pattern: /repeat(s|ing)?/i});
export const Newline = createToken({name: "Newline", pattern: /(new line|newline)/i});
export const None = createToken({name: "None", pattern: /none/i});
export const Neither = createToken({name: "Neither", pattern: /neither/i});
export const CarriageReturn = createToken({name: "Carriage Return", pattern: /carriage return/i});
export const CaseInsensitive = createToken({name: "Case Insensitive", pattern: /case insensitive/i});
export const CaseSensitive = createToken({name: "Case Sensitive", pattern: /case sensitive/i});
export const OrMore = createToken({name: "Or More", pattern: /\+/ });
export const LBracket = createToken({name: "Left Bracket", pattern: /\(/ });
export const RBracket = createToken({name: "Right Bracket", pattern: /\)/ });
export const EndOfLine = createToken({name: "EOL", pattern: /\n/ });
export const WhiteSpace = createToken({name: "Whitespace", pattern: /\s+/, group: Lexer.SKIPPED });
export const SingleLineComment = createToken({name: "Single-Line Comment", pattern: /(#|\/\/).*/, group: Lexer.SKIPPED });
export const MultilineComment = createToken({name: "Multi-Line Comment", pattern: /\/\*(.*)\*\//, line_breaks: true, group: Lexer.SKIPPED });
export const Identifier = createToken({name: "Identifier", pattern: /[a-z]\w*/i });
export const NumberLiteral = createToken({name: "Number Literal", pattern: /-?(0|[1-9]\d*)(\.\d+)?([eE][+-]?\d+)?/ });
export const StringLiteral = createToken({name: "String Literal", pattern: /"(?:[^\\"]|\\(?:[bfnrtv"\\/]|u[0-9a-f]{4}|U[0-9a-f]{8}))*"/i });
export const Indent = createToken({name: "Indent"});
export const Outdent = createToken({name: "Outdent"});
export const AllTokens = [
Zero,
One,
Two,
Three,
Four,
Five,
Six,
Seven,
Eight,
Nine,
Ten,
Optional,
Matching,
Match,
Then,
Anything,
Of,
Or,
And,
Word,
Digit,
Character,
Whitespace,
Number,
As,
If,
Start,
With,
Ends,
Otherwise,
Else,
Unless,
While,
More,
Using,
Global,
Multiline,
Exact,
Nothing,
Not,
Between,
Tab,
Linefeed,
Group,
By,
A,
The,
Exactly,
Inclusive,
Exclusive,
From,
Create,
Called,
Repeat,
Newline,
None,
Neither,
CarriageReturn,
CaseInsensitive,
CaseSensitive,
OrMore,
To,
EndOfLine,
Indent,
WhiteSpace,
SingleLineComment,
MultilineComment,
Identifier,
NumberLiteral,
StringLiteral,
];

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src/utilities.ts Normal file
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@ -0,0 +1,21 @@
export function last<T>(array: T[]) : T {
return array[array.length-1];
}
export function findLastIndex<T>(array: T[], value: T) : number {
for (let index = array.length-1; index >= 0; index--) {
if (array[index] === value) {
return index;
}
}
return -1;
}
export function findLastIndexPredicate<T>(array: T[], predicate: (x: T) => boolean) : number {
for (let index = array.length-1; index >= 0; index--) {
if (predicate(array[index])) {
return index;
}
}
return -1;
}