Need better string methods

Christian Tismer tismer at stackless.com
Sat Mar 6 22:07:57 CET 2004


William Park wrote:

...

>># Current best Python:
>>clean = [' '.join(t.split()).strip('.') for t in line.split('|')]
> 
> 
> Both Bash shell and Python can split based on regular expression.
> However, shell is not a bad alternative here:
>     tr -s ' \t' ' ' | sed -e 's/ ?| ?/|/g' -e 's/^ //' -e 's/ $//' |
>     while IFS='|' read -a clean; do
> 	...
>     done

But isn't that regex expression much harder to understand
for part-time programmers than the few Python methods?

(Quoting David's post)
"""
clean = [' '.join(t.split()).strip('.') for t in line.split('|')]

This is too much to expect of a non-programmer, even one who
undestands the methods.  The usability problems are 1) the three
variations in syntax ( methods, a list comprehension, and what *looks
like* a join function prefixed by some odd punctuation), and 2) The
order in which each step is entered at the keyboard.  ( I can show
this in step-by-step detail if anyone doesn't understand what I mean.)
3) Proper placement of parens can be confusing.
"""

Right. This quite a couple of concepts in one line, and it
might be short and efficient, but obfuscated for the none-
programmer.
Isn't this more readable? :

pieces = line.split(|)   # break at the bars
nodots  = [ piece.strip(".") for piece in pieces ] # remove leading or 
trailing dots
clean = [" ".join(words.split()) for words in nodots] # normalise spaces

Well, there is still some complexity with the join/split mess.
But still more readable than the regex?

-- 
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