replaceFirstInto

void replaceFirstInto(Sink,  R,  C,  RegEx)(ref  Sink sink,  R input,  RegEx re,  const(C)[]  format) if (isOutputRange!(Sink,  dchar)  &&  isSomeString!R
    &&  is(C :  dchar)  &&  isRegexFor!(RegEx,  R))

@trusted

A variation on replaceFirst that instead of allocating a new string on each call outputs the result piece-wise to the sink. In particular this enables efficient construction of a final output incrementally.

Like in replaceFirst family of functions there is an overload for the substitution guided by the format string and the one with the user defined callback.

void replaceFirstInto(alias  fun,  Sink,  R,  RegEx)(Sink sink,  R input,  RegEx re) if (isOutputRange!(Sink,  dchar)  &&  isSomeString!R &&  isRegexFor!(RegEx,  R))

@trusted

ditto