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export function regExpLeadsToEndlessLoop(regexp: RegExp): boolean {
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>
// against an empty string
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>
if (regexp.source === '^' || regexp.source === '^$' || regexp.source === '$' || regexp.source === '^\\s*$') {
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return false;
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}
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>
// We check against an empty string. If the regular expression doesn't advance
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>
// (e.g. ends in an endless loop) it will match an empty string.
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>
const match = regexp.exec('');
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>
return !!(match && regexp.lastIndex === 0);
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>
}
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export function joinStrings(items: (string | undefined | null | false)[], separator: string): string {