This is a recurrent situation: I want to initialize a whole bunch
of local variables in a uniform way, but after initialization, I
need to do different things with the various variables.
What I end up doing is using a dict:
d = dict()
for v in ('spam', 'ham', 'eggs'):
d[v] = init(v)
foo(d['spam'])
bar(d['ham'])
baz(d['eggs'])
This is fine, but I'd like to get rid of the tedium of typing all
those extra d['...']s.
I.e., what I would *like* to do is something closer to this:
d = locals()
for v in ('spam', 'ham', 'eggs'):
d[v] = init(v)
foo(spam)
bar(ham)
baz(eggs)
...but this results in errors like "NameError: global name 'spam' is
not defined".
But the problem is deeper than the fact that the error above would
suggest, because even this fails:
spam = ham = eggs = None
d = locals()
for v in ('spam', 'ham', 'eggs'):
d[v] = init(v)
foo(spam) # calls foo(None)
bar(ham) # calls bar(None)
baz(eggs) # calls baz(None)
In other words, setting the value of locals()['x'] does not set
the value of the local variable x.
I also tried a hack using eval:
for v in ('spam', 'ham', 'eggs'):
eval "%s = init('%s')" % (v, v)
but the "=" sign in the eval string resulted in a "SyntaxError:
invalid syntax".
Is there any way to use a loop to set a whole bunch of local
variables (and later refer to these variables by their individual
names)?
TIA!
kj
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