Function substringBefore

substringBefore(
text?: string | null,
separator?: string | null,
): string | null | undefined
Returns the substring before the first occurrence of the given separator (the separator is not returned)
Parameters
- Optionaltext: string | null
  The string to get a substring from
- Optionalseparator: string | null
  The string to search for
Returns string | null | undefined
the substring before the first occurrence of the given separator
Author
David Hsing
Example
```
substringBefore("foo/bar/foo/bar", "/");    // 'foo'
```