cmd all commands method?

[placid]

Hi all,

if i want to treat every cmdloop prompt entry as a potential command
then i need to overwrite the default() method ?

What i want to achieve is to be able to support global variable
creation for example;

res = sum 1 2

this would create a variable res with the result of the method
do_sum() ?

then would i be able to run;

sum a 5

this would return 8 or an error saying that res is not defined


Cheers

[placid]

Re: cmd all commands method?


placid wrote:

Hi all,
>
if i want to treat every cmdloop prompt entry as a potential command
then i need to overwrite the default() method ?
>
What i want to achieve is to be able to support global variable
creation for example;
>
res = sum 1 2
>
this would create a variable res with the result of the method
do_sum() ?
>
then would i be able to run;
>
sum a 5

this should have been,

sum res 5

>
this would return 8 or an error saying that res is not defined
>
>
Cheers

[Bjoern Schliessmann]

Re: cmd all commands method?

placid wrote:

if i want to treat every cmdloop prompt entry as a potential
command then i need to overwrite the default() method ?

Excuse me, what's a cmdloop prompt? What's the "default() method"?

What i want to achieve is to be able to support global variable
creation for example;
>
res = sum 1 2
>
this would create a variable res with the result of the method
do_sum() ?
>
then would i be able to run;
>
sum a 5
>
this would return 8 or an error saying that res is not defined

Are you sure you're talking about Python here?

Regards,


Björn

--
BOFH excuse #7:

poor power conditioning

[Michele Simionato]

Re: cmd all commands method?

On Feb 17, 11:44 pm, Bjoern Schliessmann <usenet-
mail-0306.20.chr0n.. .@spamgourmet.c omwrote:

placid wrote:

if i want to treat every cmdloop prompt entry as a potential
command then i need to overwrite the default() method ?

>
Excuse me, what's a cmdloop prompt? What's the "default() method"?
>

What i want to achieve is to be able to support global variable
creation for example;

>

res = sum 1 2

>

this would create a variable res with the result of the method
do_sum() ?

>

then would i be able to run;

>

sum a 5

>

this would return 8 or an error saying that res is not defined

>
Are you sure you're talking about Python here?

Yes, he is talking about the cmd module: http://docs.python.org/dev/lib/Cmd-objects.html.
However that module was never intended as a real interpreter, so
defining variables
as the OP wants would require some work.

Michele Simionato

[placid]

Re: cmd all commands method?

On Feb 18, 7:17 pm, "Michele Simionato" <michele.simion ...@gmail.com>
wrote:

On Feb 17, 11:44 pm, Bjoern Schliessmann <usenet-
>
>
>
mail-0306.20.chr0n.. .@spamgourmet.c omwrote:

placid wrote:

if i want to treat every cmdloop prompt entry as a potential
command then i need to overwrite the default() method ?

>

Excuse me, what's a cmdloop prompt? What's the "default() method"?

>

What i want to achieve is to be able to support global variable
creation for example;

>

res = sum 1 2

>

this would create a variable res with the result of the method
do_sum() ?

>

then would i be able to run;

>

sum a 5

>

this would return 8 or an error saying that res is not defined

>

Are you sure you're talking about Python here?

>
Yes, he is talking about the cmd module:http://docs.python.org/dev/lib/Cmd-objects.html.
However that module was never intended as a real interpreter, so
defining variables
as the OP wants would require some work.
>
Michele Simionato

How much work does it require ?

[Peter Otten]

Re: cmd all commands method?

placid wrote:

On Feb 18, 7:17 pm, "Michele Simionato" <michele.simion ...@gmail.com>
wrote:

>On Feb 17, 11:44 pm, Bjoern Schliessmann <usenet-
>>
>>
>>
>mail-0306.20.chr0n.. .@spamgourmet.c omwrote:

placid wrote:
if i want to treat every cmdloop prompt entry as a potential
command then i need to overwrite the default() method ?

>>

Excuse me, what's a cmdloop prompt? What's the "default() method"?

>>

What i want to achieve is to be able to support global variable
creation for example;

>>

res = sum 1 2

>>

this would create a variable res with the result of the method
do_sum() ?

>>

then would i be able to run;

>>

sum a 5

>>

this would return 8 or an error saying that res is not defined

>>

Are you sure you're talking about Python here?

>>
>Yes, he is talking about the cmd
>module:http://docs.python.org/dev/lib/Cmd-objects.html. However that
>module was never intended as a real interpreter, so defining variables
>as the OP wants would require some work.
>>
> Michele Simionato

>
How much work does it require ?

Too much. However, here's how far I got:

import cmd
import shlex

DEFAULT_TARGET = "_"

def number(arg):
for convert in int, float:
try:
return convert(arg)
except ValueError:
pass
return arg

class MyCmd(cmd.Cmd):
def __init__(self, *args, **kw):
cmd.Cmd.__init_ _(self, *args, **kw)
self.namespace = {}
self.target = DEFAULT_TARGET
def precmd(self, line):
parts = line.split(None , 2)
if len(parts) == 3 and parts[1] == "=":
self.target = parts[0]
return parts[2]
self.target = DEFAULT_TARGET
return line
def resolve(self, arg):
args = shlex.split(arg )
result = []
for arg in args:
try:
value = self.namespace[arg]
except KeyError:
value = number(arg)
result.append(v alue)
return result
def calc(self, func, arg):
try:
result = self.namespace[self.target] = func(self.resol ve(arg))
except Exception, e:
print e
else:
print result

def do_sum(self, arg):
self.calc(sum, arg)
def do_max(self, arg):
self.calc(max, arg)
def do_print(self, arg):
print " ".join(str( arg) for arg in self.resolve(ar g))
def do_values(self, arg):
pairs = sorted(self.nam espace.iteritem s())
print "\n".join(" %s = %s" % nv for nv in pairs)
def do_EOF(self, arg):
return True

if __name__ == "__main__":
c = MyCmd()
c.cmdloop()

Peter

[Michele Simionato]

Re: cmd all commands method?

On Feb 18, 10:49 am, "placid" <Bul...@gmail.c omwrote:

On Feb 18, 7:17 pm, "Michele Simionato" <michele.simion ...@gmail.com>
>

Yes, he is talking about the cmd module:http://docs.python.org/dev/lib/Cmd-objects.html.
However that module was never intended as a real interpreter, so
defining variables
as the OP wants would require some work.

>

Michele Simionato

>
How much work does it require ?

Have you ever written an interpreter? It is a nontrivial job.

Michele Simionato

[placid]

Re: cmd all commands method?

On Feb 18, 8:59 pm, "Michele Simionato" <michele.simion ...@gmail.com>
wrote:

On Feb 18, 10:49 am, "placid" <Bul...@gmail.c omwrote:
>

On Feb 18, 7:17 pm, "Michele Simionato" <michele.simion ...@gmail.com>

>

Yes, he is talking about the cmd module:http://docs.python.org/dev/lib/Cmd-objects.html.
However that module was never intended as a real interpreter, so
defining variables
as the OP wants would require some work.

>

Michele Simionato

>

How much work does it require ?

>
Have you ever written an interpreter? It is a nontrivial job.
>
Michele Simionato

No i have never written an interpreter and i can just imagine how much
work/effort is needed to write something like that.

If anyone can provide a suggestion to replicate the following Tcl
command in Python, i would greatly appreciate it.

namespace eval foo {
variable bar 12345
}

what this does is create a namespace foo with the variable bar set to
12345.

http://aspn.activestate.com/ASPN/docs/ActiveTcl/8.4/tcl/TclCmd/variable.htm

The code provided by Peter Otten is a good start for me. Cheers for
that!


Cheers

[Gabriel Genellina]

Re: cmd all commands method?

En Mon, 19 Feb 2007 00:08:45 -0300, placid <Bulkan@gmail.c omescribió:

If anyone can provide a suggestion to replicate the following Tcl
command in Python, i would greatly appreciate it.
>
namespace eval foo {
variable bar 12345
}
>
what this does is create a namespace foo with the variable bar set to
12345.

Python namespaces are simple dictionaries. See the eval function.

pys = "3+x**2"
pyfreevars = {"x": 2}
pyeval(s, {}, freevars)
7

--
Gabriel Genellina