propertyAccess.js
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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const SAFE_IDENTIFIER = /^[_a-zA-Z$][_a-zA-Z$0-9]*$/;
const RESERVED_IDENTIFIER = new Set([
"break",
"case",
"catch",
"class",
"const",
"continue",
"debugger",
"default",
"delete",
"do",
"else",
"export",
"extends",
"finally",
"for",
"function",
"if",
"import",
"in",
"instanceof",
"new",
"return",
"super",
"switch",
"this",
"throw",
"try",
"typeof",
"var",
"void",
"while",
"with",
"enum",
// strict mode
"implements",
"interface",
"let",
"package",
"private",
"protected",
"public",
"static",
"yield",
"yield",
// module code
"await",
// skip future reserved keywords defined under ES1 till ES3
// additional
"null",
"true",
"false"
]);
const propertyAccess = (properties, start = 0) => {
let str = "";
for (let i = start; i < properties.length; i++) {
const p = properties[i];
if (`${+p}` === p) {
str += `[${p}]`;
} else if (SAFE_IDENTIFIER.test(p) && !RESERVED_IDENTIFIER.has(p)) {
str += `.${p}`;
} else {
str += `[${JSON.stringify(p)}]`;
}
}
return str;
};
module.exports = propertyAccess;