Hello

The developer of a perl application that we run here has been asked about some problems we are facing with it. In a recent e-mail he wrote us about why he treated a variable in a special way:

See how I've wrapped $user_id in quotes like "$user_id" to force string context. When the user ID is represented as a number, the internal representation of the number causes rounding because of lost precision.

Now, I am not an expert at all about perl internals. But, apart of the well known cases where zero is involved, like:

bronto@brabham:~$ perl -e 'print "0.00"? "True\n": "False\n"'
True
bronto@brabham:~$ perl -e 'print 0.00? "True\n": "False\n"'
False

[download]

...Perl has always been smart enough to make sense of how I was using numbers in scalar variables.

Does that assertion make sense? Even if $user_id has no decimal digits?

Thanks for any advice

Ciao!
--bronto

The very nature of Perl to be like natural language--inconsistant and full of dwim and special cases--makes it impossible to know it all without simply memorizing the documentation (which is not complete or totally correct anyway).
--John M. Dlugosz

In reply to "force string context"? by bronto

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