Please start a new email when starting a new topic. Otherwise it gets
linked to the previous one in email clients that follow threads!
To avoid that here I am responding in a new email. Also fixed spelling
in subject.
Albert-Jan Roskam wrote:
Hi,
I was playing with the code below, and I was wondering if there was a way to
populate the dictionary called 'commands' (in the function 'check_command()').
Suppose I would add another function, which I would also like to store as a
value in 'commands', could it simply be programmed, or would every
update/addition require the definition of the dictionary to be extended?
It would be most desirable if one could simply add another function without there being the need to touch any of the other code.
Here's how I'd do it. Others may have other solutions.
Put the command functions in a separate module, e.g., commands.py:
# -------- code ---------------
def foo (a):
return "foo" * a
def bletch (q):
for i in range(20):
print i * q
def stilton (n):
print "yes sir, " * n
def romans (z):
print "what have the romans really done for us?\n" * z
# -------- end code ---------------
Put the "main" program (in another module) e.g., main.py:
# -------- code ---------------
import commands
import inspect
cmds = inspect.getmembers(commands, inspect.isfunction)
num_cmds = len(cmds)
option_list = "|".join(str(c) for c in range(1, num_cmds+1))
prompt = "choose an option [%s]: " % option_list
def check_command():
while True:
select = raw_input(prompt)
try:
command = cmds[int(select)][1]
except ValueError:
print "non-numeric option (%s)" % select
except IndexError:
print "option out of range (%s)" % select
else:
check_parameter(command)
break
def check_parameter(command):
while True:
parameter = raw_input("choose a parameter [integer]: ")
if parameter.isdigit():
command(int(parameter))
break
else:
print "illegal parameter (%s)" % parameter
check_command()
# -------- end code ---------------
cmds is a list similar to:
[('bletch', <function bletch at 0x011BA2B0>),
('foo', <function foo at 0x011AF9B0>),
('romans', <function romans at 0x011BA330>),
('stilton', <function stilton at 0x011BA2F0>)]
--
Bob Gailer
Chapel Hill NC
919-636-4239
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