avoid the redefinition of a function

[Tim Chase]

On 09/12/12 11:56, Jabba Laci wrote:
>> For example:
>>
>> def install_java():
>>    pass
>>
>> def install_tomcat():
>>    pass
> 
> Thanks for the answers. I decided to use numbers in the name of the
> functions to facilitate function calls. Now if you have this menu
> option for instance:
> 
> (5) install mc
> 
> You can type just "5" as user input and step_5() is called
> automatically. If I use descriptive names like install_java() then
> selecting a menu point would be more difficult. And I don't want users
> to type "java", I want to stick to simple numbers.

You can do something like the below that I tossed together in a
couple minutes.  It sniffs for globals callables (usually functions,
though could be objects with a __call__ method) that are named
"install_*" and then maps the user's numeric answer to the
corresponding function and calls it.

-tkc

import sys
PREFIX = "install_"
def install_java(*args, **kwargs):
    print "Java!"
def install_tomcat(*args, **kwargs):
    print "Tomcat!"
def install_mc(*args, **kwargs):
    print "mc!"
def install_exit(*args, **kwargs):
    sys.exit(0)

functions = [
    (name, value)
    for name, value
    in sorted(globals().items())
    if name.startswith(PREFIX)
        and callable(value)
    ]
dispatch = dict(
    (i+1, value)
    for i, (name, value)
    in enumerate(functions)
    )

for i, (name, value) in enumerate(functions):
    print("%i) %s" % (i+1, name[len(PREFIX):]))

while True:
    choice = raw_input("Choose to install/quit: ")
    try:
        i = int(choice)
    except:
        continue
    if i in dispatch:
        dispatch[i]("some args")
    else:
        print("Please choose a valid option")