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chrono-node

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A natural language date parser in Javascript

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import { MONTH_DICTIONARY } from "../constants"; import { ParsingContext } from "../../../chrono"; import { findYearClosestToRef } from "../../../calculation/years"; import { matchAnyPattern } from "../../../utils/pattern"; import { YEAR_PATTERN, parseYear } from "../constants"; import { AbstractParserWithWordBoundaryChecking } from "../../../common/parsers/AbstractParserWithWordBoundary"; const PATTERN = new RegExp( `(${matchAnyPattern(MONTH_DICTIONARY)})` + `\\s*` + `(?:` + `[,-]?\\s*(${YEAR_PATTERN})?` + ")?" + "(?=[^\\s\\w]|\\s+[^0-9]|\\s+$|$)", "i" ); const MONTH_NAME_GROUP = 1; const YEAR_GROUP = 2; /** * The parser for parsing month name and year. * - januari, 2012 * - januari 2012 * - januari */ export default class NLMonthNameParser extends AbstractParserWithWordBoundaryChecking { innerPattern(): RegExp { return PATTERN; } innerExtract(context: ParsingContext, match: RegExpMatchArray) { const components = context.createParsingComponents(); components.imply("day", 1); const monthName = match[MONTH_NAME_GROUP]; const month = MONTH_DICTIONARY[monthName.toLowerCase()]; components.assign("month", month); if (match[YEAR_GROUP]) { const year = parseYear(match[YEAR_GROUP]); components.assign("year", year); } else { const year = findYearClosestToRef(context.refDate, 1, month); components.imply("year", year); } return components; } }