use strings to call functions
in [Python]
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From: OdarR on 8 Feb 2010 14:28 On 8 fév, 11:57, Klaus Neuner <klausneune...(a)googlemail.com> wrote: > Hello, > > I am writing a program that analyzes files of different formats. I > would like to use a function for each format. Obviously, functions can > be mapped to file formats. E.g. like this: > > if file.endswith('xyz'): > xyz(file) > elif file.endswith('abc'): > abc(file) > > ... > > Yet, I would prefer to do something of the following kind: > > func = file[-3:] > apply_func(func, file) > > Can something of this kind be done in Python? and with eval(), did you try ? import sys def functext(): print "texte" def funcdoc(): print "doc" def funcabc(): print "abc" if __name__ == "__main__": #replace filename with suitable value filename = sys.argv[1].split('.')[1] try: eval('func' + filename + '()') except: print 'error'
From: Gary Herron on 8 Feb 2010 14:47 OdarR wrote: > On 8 fév, 11:57, Klaus Neuner <klausneune...(a)googlemail.com> wrote: > >> Hello, >> >> I am writing a program that analyzes files of different formats. I >> would like to use a function for each format. Obviously, functions can >> be mapped to file formats. E.g. like this: >> >> if file.endswith('xyz'): >> xyz(file) >> elif file.endswith('abc'): >> abc(file) >> >> ... >> >> Yet, I would prefer to do something of the following kind: >> >> func = file[-3:] >> apply_func(func, file) >> >> Can something of this kind be done in Python? >> I may have missed a bit of this thread -- so I have to ask: Has anyone mentioned using getattr yet? It's a way of looking up *any* attribute using a string to specify the name. Like this for your particular example: class Functions: # This could be a module instead of a class def xyz(...): ... def abc(...): ... ... and so on ... ext = os.path.splitext(file) # Parses out the extension fn = getattr(Functions, ext) # Lookup the correct function fn(...) # and call it Gary Herron
From: Aahz on 8 Feb 2010 16:28 In article <0efe23a6-b16d-4f92-8bc0-12d056bf599d(a)z26g2000yqm.googlegroups.com>, OdarR <olivier.darge(a)gmail.com> wrote: > >and with eval(), did you try ? WARNING: eval() is almost always the wrong answer to any question -- Aahz (aahz(a)pythoncraft.com) <*> http://www.pythoncraft.com/ import antigravity
From: OdarR on 8 Feb 2010 16:39 On 8 fév, 22:28, a...(a)pythoncraft.com (Aahz) wrote: > In article <0efe23a6-b16d-4f92-8bc0-12d056bf5...(a)z26g2000yqm.googlegroups..com>, > > OdarR <olivier.da...(a)gmail.com> wrote: > > >and with eval(), did you try ? > > WARNING: eval() is almost always the wrong answer to any question warning : it works ! another question ? > -- > Aahz (a...(a)pythoncraft.com) <*> http://www.pythoncraft.com/ > > import antigravity
From: Aahz on 8 Feb 2010 17:43
In article <5790c33c-13d0-4596-91b0-b3c9aeebf637(a)f8g2000yqn.googlegroups.com>, OdarR <olivier.darge(a)gmail.com> wrote: >On 8 f=E9v, 22:28, a...(a)pythoncraft.com (Aahz) wrote: >> In article <0efe23a6-b16d-4f92-8bc0-12d056bf5...(a)z26g2000yqm.googlegroups= >.com>, >> OdarR =A0<olivier.da...(a)gmail.com> wrote: >>> >>>and with eval(), did you try ? >> >> WARNING: eval() is almost always the wrong answer to any question > >warning : it works ! Works for what? -- Aahz (aahz(a)pythoncraft.com) <*> http://www.pythoncraft.com/ import antigravity |