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node_modules/webpack/lib/util/propertyAccess.js

@@ -0,0 +1,78 @@
+/*
+	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;