static if(!(idx < 0))
static if(!(idx1 >= fmt.length - 1))
static if(!(fmt[idx2 + 1] == 's'))
static if(!(fmt[idx2 + 1] == 'c'))
static if(!(fmt[idx2 + 1] == 'n'))
static if(!(fmt[idx2 + 1] == 'd'))
static if(!(fmt[idx2 + 1] == 'x'))
static if(!(fmt[idx2 + 1] == 'b'))
static if(fmt[idx2 + 1] == 'p')