# replaceFirst method

String replaceFirst (Pattern from, String to, [ int startIndex = 0 ])

Returns a new string in which the first occurrence of `from` in this string is replaced with `to`, starting from `startIndex`:

    '0.0001'.replaceFirst(new RegExp(r'0'), ''); // '.0001'
    '0.0001'.replaceFirst(new RegExp(r'0'), '7', 1); // '0.7001'

## Implementation

    String replaceFirst(Pattern from, String to, [int startIndex = 0]);