Compute in one pass 3 tokens position

[bioinfornatics]

Hi,
I would like to know how compute in on pass 3 tokens position in a
sequence.
curently i do:
File f = File( "reader.d", "r" );
scope(exit) f.close();
char[1024] buffer;
char[] content = f.rawRead(buffer);
char[sizediff_t] token = ['(', '{', ';'];
auto position = map!( a => content.countUntil( a ) )( [ ['('], ['{'],
[';'] ] );


if i use reduce instead map the build fail