Re^2: How to check if a scalar value is numeric or string?

Actually the exact requirement is as below:

1. Use GetOptions to process the input command line.
2. Do the required validation. This will result in modifying the command line paramteres
   and resultant will be stored in a hash.
3. Use this hash in order to form the command line again.

The problem is while doing the 3rd step, I need to distinguish if a given argument is a toggle or a parameter. So, I want to distinguish between 1( toggle ) and '1'( argument ).

Comment on Re^2: How to check if a scalar value is numeric or string?

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Re^3: How to check if a scalar value is numeric or string? by ikegami (Patriarch) on Aug 27, 2009 at 15:02 UTC
Why don't you save a copy of the command line before calling `GetOptions`? If you can't because you're rearranging the command line somehow, you'll need to pass your reconstructor some of the information you pass to `GetOptions` (as in, whether a parameter is a toggle or takes a value).	[reply] [d/l] [select]
Re^4: How to check if a scalar value is numeric or string? by bgupta (Novice) on Aug 27, 2009 at 15:23 UTC
Since I am modifying the resultant hash drastically, it is very difficult to keep track of the changes in the hash.	[reply]
Re^5: How to check if a scalar value is numeric or string? by ikegami (Patriarch) on Aug 27, 2009 at 16:00 UTC
Since I am modifying the resultant hash drastically, Simply looking at the variable can change its internal format, so you don't want to rely on that. `$ perl -MDevel::Peek -le'$\|=1; $x=1; Dump $x; print "x=$x"; Dump $x' SV = IV(0x816a438) at 0x814f6cc REFCNT = 1 FLAGS = (IOK,pIOK) <--- $x is a number IV = 1 x=1 SV = PVIV(0x8150b10) at 0x814f6cc REFCNT = 1 FLAGS = (IOK,POK,pIOK,pPOK) <--- $x is a number and a string IV = 1 PV = 0x81651b8 "1"\0 CUR = 1 LEN = 4` [download] If you wanted to spend some effort, you could actually use the list you passed to `GetOptions`. If not, the following could do with very little effort: `sub reconstruct_toggle { ... } sub reconstruct_with_val { ... } sub reconstruct_opt_val { ... } reconstruct( foo => \&reconstruct_toggle, bar => \&reconstruct_with_val, special => sub { ... }, );` [download]	[reply] [d/l] [select]
Re^3: How to check if a scalar value is numeric or string? by bv (Friar) on Aug 27, 2009 at 15:35 UTC
Your requirement mentions GetOptions. Does this mean you are using Getopt::Long? If so, how are you specifying the option? `opt=s, opt:s, opt=i, opt:i, opt`, etc? Getopt::Long is usually good about setting sane values. If you asked for an integer with :i, it will set your value to 0 if there was no argument given, so you can test with `exists` to see if it was set. `$,=' ';$\=',';$_=[qw,Just another Perl hacker,];print@$_;`	[reply] [d/l] [select]
Re^3: How to check if a scalar value is numeric or string? by GrandFather (Saint) on Aug 27, 2009 at 21:30 UTC
If you know at the point where you store the value that it is a 1 or a '1', then store '1' (including the quote marks) for the string version. True laziness is hard work	[reply]