public parseSearchRequest(): RegExp {
		if (this.searchString === '') {
			return null;
		}

		// Try to create a RegExp out of the params
		let multiline: boolean;
		if (this.isRegex) {
			multiline = SearchParams._isMultilineRegexSource(this.searchString);
		} else {
			multiline = (this.searchString.indexOf('\n') >= 0);
		}

		let regex: RegExp = null;
		try {
			regex = strings.createRegExp(this.searchString, this.isRegex, {
				matchCase: this.matchCase,
				wholeWord: this.wholeWord,
				multiline,
				global: true
			});
		} catch (err) {
			return null;
		}

		if (!regex) {
			return null;
		}

		return regex;
	}

	private _rangeIsMatch(range:Range): boolean {
		let selection = this._editor.getSelection();
		let selectionText = this._editor.getModel().getValueInRange(selection);
		let regexp = strings.createRegExp(this._state.searchString, this._state.isRegex, this._state.matchCase, this._state.wholeWord, true);
		let m = selectionText.match(regexp);
		return (m && m[0].length === selectionText.length);
	}

	private getReplaceString(matchedString:string): string {
		if (!this._state.isRegex) {
			return this._state.replaceString;
		}
		let regexp = strings.createRegExp(this._state.searchString, this._state.isRegex, this._state.matchCase, this._state.wholeWord, true);
		// Parse the replace string to support that \t or \n mean the right thing
		let parsedReplaceString = parseReplaceString(this._state.replaceString);
		return matchedString.replace(regexp, parsedReplaceString);
	}

	public parseSearchRequest(): SearchData {
		if (this.searchString === '') {
			return null;
		}

		// Try to create a RegExp out of the params
		let multiline: boolean;
		if (this.isRegex) {
			multiline = SearchParams._isMultilineRegexSource(this.searchString);
		} else {
			multiline = (this.searchString.indexOf('\n') >= 0);
		}

		let regex: RegExp = null;
		try {
			regex = strings.createRegExp(this.searchString, this.isRegex, {
				matchCase: this.matchCase,
				wholeWord: false,
				multiline: multiline,
				global: true
			});
		} catch (err) {
			return null;
		}

		if (!regex) {
			return null;
		}

		let canUseSimpleSearch = (!this.isRegex && !multiline);
		if (canUseSimpleSearch && this.searchString.toLowerCase() !== this.searchString.toUpperCase()) {
			// casing might make a difference
			canUseSimpleSearch = this.matchCase;
		}

		return new SearchData(regex, this.wordSeparators ? getMapForWordSeparators(this.wordSeparators) : null, canUseSimpleSearch ? this.searchString : null);
	}

function createOrRegex(pieces:string[]): RegExp {
	let regexStr = `(${pieces.map(strings.escapeRegExpCharacters).join(')|(')})`;
	return strings.createRegExp(regexStr, true, false, false, false);
}

function createBracketOrRegExp(pieces: string[]): RegExp {
	let regexStr = `(${pieces.map(prepareBracketForRegExp).join(')|(')})`;
	return strings.createRegExp(regexStr, true);
}