klyn.regex.RegEx.replaceFirst
method
public native replaceFirst(input as String, replacement as String) as String:
Description

Replaces the first occurrence of the pattern with a replacement string.

Parameters
ParameterDescription
inputThe string where the replacement will be performed.
replacementThe replacement string.
Returns

The string after the replacement.

Example
regex = RegEx(r"\d+")
result = regex.replaceFirst("123 abc 456", "#")  # result will be "# abc 456"