kj wrote:
In Perl, one can label loops for finer flow control. For example:
X: for my $x (@X) {
Y: for my $y (@Y) {
for my $z (@Z) {
next X if test1($x, $y, $z);
next Y if test2($x, $y, $z);
frobnicate($x, $y, $z);
}
glortz($x, $y);
}
splat($x);
}
What's considered "best practice" in the Python world for this sort
of situation? The only approach I can think of requires setting
up indicator variables that must be set and tested individually;
e.g.
for x in X:
next_X = False
for y in Y:
next_Y = False
for z in Z:
if test1(x, y, z):
next_X = True
break
if test2(x, y, z):
next_Y = True
break
frobnicate(x, y, z)
if next_X:
break
if next_Y:
continue
glortz(x, y)
if next_X:
continue
splat(x)
Whereas I find the Perl version reasonably readable, the Python
one I find nearly incomprehensible. In fact, I'm not even sure
that the Python version faithfully replicates what the Perl one is
doing!
Is there a better approach?
1. Put inner loops in a function and return instead of break.
2. Put inner loops in
try:
for..
for
if cond: raise Something
# or do operation that raises exception if cond is true
except e:
whatever
tjr
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