Griswolf: format

2010-06-29T04:13:15Z

format

Griswolf: create example

2010-06-29T04:11:28Z

create example

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[[Python|''back to Python examples'']]
----
In many languages, there is a switch or case statement. Python appears not to have that, so you will see a lot of if/elif/elif/.../else . There is a better way using a dict. 
For concreteness, lets mimic this C code:
<syntaxhighlight lang="c">
int count_of_bs = 0
switch(a) {
case 'a': call_a(a); break;
case 'b': ++count_of_bs; break
default: call_other(a); break;
}
</syntaxhighlight>
Here it is in Python (with function definitions and a few quick tests)
=== switchExample.py ===
<syntaxhighlight lang="python">
count_of_bs = 0
# these functions would have to be defined in any case.
def call_a(a):
print 'a called with %s'%str(a)

def call_other(a):
print 'otherwise, with %s'%str(a)

#this function is 'overhead' to make the switch statement work
def do_b(a):
global count_of_bs
count_of_bs += 1

# this is the declaration of the switch
switch = {
'a':call_a,
'b': do_b,
}
# run some test cases. Note that we handle non-scalars just fine
print ('count_of_bs %s'%count_of_bs)
for tc in ['b', 'a','b','c','b','alphabet',(99,'bottles','beer'),'b']:
# this is how you use it
switch.get(tc,call_other)(tc)
print ('count_of_bs %s'%count_of_bs)

"""Output:
count_of_bs 0
a called with a
otherwise, with c
otherwise, with alphabet
otherwise, with (99, 'bottles', 'beer')
count_of_bs 4
"""
</syntaxhighlight>
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[[Python|''back to Python examples'']]

@@ Line 1: / Line 1: @@
 [[Python|<font size='-2'>''back to Python examples''</font>]]
 ----
-In many languages, there is a switch or case statement. Python appears not to have that, so you will see a lot of if/elif/elif/.../else . There is a better way using a dict.<br />
+In many languages, there is a switch or case statement. Python appears not to have that, so you will often see a lot of <code>if/elif/elif/.../else</code> blocks. There is a better way using a dict.<br />
 For concreteness, lets mimic this C code:
 <syntaxhighlight lang="c">

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