Odd Errors

Aaron "Castironpi" Brady castironpi at gmail.com
Mon Sep 29 02:32:56 CEST 2008


On Sep 28, 7:13 pm, alex23 <wuwe... at gmail.com> wrote:
> The problem is with this:
>
> >         lines = lines.append(inLine)
>
> The append method of a list modifies the list in-place, it doesn't
> return a copy of the list with the new element appended. In fact, it
> returns None, which it then attaches the label 'lines' to, so the next
> iteration through it tries to call None.append...
>
> Replace the line with:
>
>     lines.append(inLine)

Do you ever want to scream from the rooftops, "'append' operates by
side-effect!"?



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