How to print something only if it exists?

[Joshua Landau]

On 6 September 2012 18:59, <tinnews at isbd.co.uk> wrote:

> I want to print a series of list elements some of which may not exist,
> e.g. I have a line:-
>
>      print day, fld[1], balance, fld[2]
>
> fld[2] doesn't always exist (fld is the result of a split) so the
> print fails when it isn't set.
>

What I might do is simply make a class that wraps the list.

class SafeIndex:
    def __init__(self, lst, safety=""):
        self.list = lst
        self.safety = ""
    def __getitem__(self, n):
        try:
            return self.list[n]
        except IndexError:
            return self.safety

si = SafeIndex(range(20))

Then just index the SafeIndex with the print and abandon it after.
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