Can I Replace Part of a Python "If" Statement with a Variablized String Literal? -

i have long question may short answer.

i'm new python (almost 2 weeks, now) i've used vbscript many years understand many of basic concepts.

i've searched stack overflow , internet solution haven't been able find anything; i'm not sure if possible in python, i'd bit surprised if it's not. i've written file-search program using python3 allows users search computer files. user can choose search based on several different parameters: name, size range, date-modified range and, non-linux systems, date-created range. search functionaly works quite each individual parameter combinations of parameters (which, way, in no small part many answers / discussions i've found here on stack overflow). problem actual search rather inelegant and, believe, slower be. program uses flags (not true python flags, that's happen call them) set search options. let me illustrate pseudo code:

    # variables values user entry     sname = "test" # string search     sminsize = 2 # minimum search-by size in mb     smaxsize = 15 # maximum search-by size in mb     smodded1 = 2008-01-23 # earliest modified-by date     smodded2 = 2017-08-22 # latest modified-by date      screated1 = 2008-01-23 # earliest created-by date     screated2 = 2017-08-22 # latest created-by date      # search parameters - choosing 1 of these changes value 0 1:     flagname = 0 # search name     flagsize = 0 # search size     flagmodified = 0 # search last modified date     flagcreated = 0 # search last created date      root, dirs, files in os.walk(strpath, followlinks=false):         fname in files:             filedate = os.path.getmtime(fname)             filesize = os.stat(fname).st_size             if flagname = 1:                     if fname.find(sname) > 0:                         do_stuff             elif flagsize = 1:                             if sminsize < filesize < smaxsize:                         do_stuff             elif flagname = 1 , flagsize = 1:                     if fname.find(sname) > 0 , if sminsize < filesize < smaxsize:                         do_stuff     ... etc 

that's 3 possible combinations - there 14 total. while don't have problem typing combinations out, believe severely impact speed , efficiency of search.

i've thought of solution bit more elegant , execute faster, still think there's better method:

    if flagname = 1:         root, dirs, files in os.walk(strpath, followlinks=false):             fname in files:                 filedate = os.path.getmtime(fname)                 filesize = os.stat(fname).st_size                 if fname.find(sname) > 0:                     do_stuff      elif flagname = 1 , flagsize = 1:         root, dirs, files in os.walk(strpath, followlinks=false):             fname in files:                 filedate = os.path.getmtime(fname)                 filesize = os.stat(fname).st_size                 if fname.find(sname) > 0 , if sminsize < filesize < smaxsize:                     do_stuff     ... etc 

again, bit more elegant , (i believe) great deal more efficient, still not ideal. i'd create 1 "if" statement based on user's search criteria , use conduct search (note similar possible in vbscript). these statements go before search statements take place:

possible option 1:

    if flagname = 1:         iclause = "fname.find(sname) > 0"     elif flagname = 1 , flagsize = 1:         iclause = "fname.find(sname) > 0 , if sminsize < filesize < smaxsize"     ... etc 

possible option 2:

    flagclause = 0     if flagname = 1:         iclause = "fname.find(sname) > 0"         flagclause = flagclause + 1     if flagclause = 0         iclause = "sminsize < filesize < smaxsize"     else:         iclause = iclause + "and sminsize < filesize < smaxsize"         flagclause = flagclause + 1     ... etc 

and plug "iclause" in search statement so:

    root, dirs, files in os.walk(strpath, followlinks=false):         fname in files:             filedate = os.path.getmtime(fname)             filesize = os.stat(fname).st_size             if **iclause**:                 do_stuff 

this streamline code, making easier read , maintain , (i believe) make more efficient , speedy.

is possible python?

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edit:

i thank of taking time read lengthy question, don't believe got asking - due (over)verbosity.

i know how implement following:

    = "sminsize < filesize < smaxsize"     b = "and sminsize < filesize < smaxsize"     iclause = a+b 

then plug 'iclause' "if" statement follows:

    if iclause:         do_stuff 

this turning string literal variable, using variablized (probably not real word) string literal statement. hope clearer.

create predicate function, 1 each case. determine cases you're using , use associated predicate. collect chosen predicates in list (or compose them new predicate) apply in loop:

predicates = [] if flagname:     predicates.append(lambda filename: filename.find(sname) > 0) if flagsize:     predicates.append(lambda filename: sminsize < os.stat(filename).st_size < smaxsize) if flagmodified:     predicates.append(lambda filename: smodded1 < os.path.getmtime(filename) < smodded2) if flagcreated:     predicates.append(lambda filename: screated1 < os.path.getctime(filename) < screated2)  root, dirs, files in os.walk(strpath, followlinks=false):     fname in files:         if all(p(fname) p in predicates):             # stuff 

you may want use named function instead of lambda depending on preferences. , more complex scenarios, may want implement these functors instead.

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