Despite the warnings above there may be times, particularly when using this n-tuple syntax to write FLTR banks (see section 9.1), when quite complicated expressions may be unavoidable. With a little effort is should be possible to keep such banks readable. Consider this FORTRAN fragment:-
if ( flag .lt. 1 ) then
* Deal with flag < 1
...
elseif ( flag .eq. 1 ) then
* Deal with flag = 1
...
else
* All other cases come here.
...
* endif
in n-tuple syntax, this could be written:-
'_flag_if:
' lt flag, 1; '
'_ jump_false _flag_elseif; '
#. Deal with flag < 1
...
'_ jump flag_endif; '
'_flag_elseif:
'- eq flag, 1; '
'- jump_false _flag_else; '
#. Deal with flag = 1
...
' jump flag_endif; '
'_flag_else: '
#. All other cases come here.
...
'_flag_endif: '
The initial _flag_if: doesn't do anything except indicate the start of
an IF-THEN-ELSE-CONSTRUCT with the remaining sections marked by _flag_*
labels.