On Fri, Nov 6, 2009 at 2:04 AM, tom smith <climbingpartn...@gmail.com>wrote:
>
>
> On Fri, Nov 6, 2009 at 12:15 AM, John W. Krahn <jwkr...@shaw.ca> wrote:
>
>> Michael Alipio wrote:
>>
>>> Hi,
>>>
>>
>> Hello,
>>
>>
>> if I have a script that accepts any combination of the 5 or maybe even
>>> more options, say, option1, option2, option3...
>>>
>>>
>>> Now, after collecting the options, for each option, there is a
>>> corresponding regexp pattern. I will then build an if statement, where
>>> the test should be, all the options entered must match (&&) otherwise,
>>> return false.
>>> I'm thinking this can only be done by nested if's:
>>>
>>> if ($word =~ /$option1/ && $word =~ /$option2){
>>> if ($word =~ /$option3/ && $word =~ /$option4){
>>> if ($word =~ /$optionN/){
>>> print "All pattern matched!\n";
>>> }
>>> }
>>> }
>>>
>>>
>>> Now I'm thinking, it is quite impossible to dynamically create all
>>> those if tests. Perhaps I can just open a file for writing, write a
>>> new perl script which will have those codes, and execute it at the end.
>>> Is there a better way of doing this?
>>>
>>
>> You could use the Getopt::Long module to get multiple options into an
>> array:
>>
>> perldoc Getopt::Long
>> [ snip ]
>> Options with multiple values
>> Options sometimes take several values. For example, a program could
>> use multiple directories to search for library files:
>>
>> --library lib/stdlib --library lib/extlib
>>
>> To accomplish this behaviour, simply specify an array reference as
>> the destination for the option:
>>
>> GetOptions ("library=s" => \...@libfiles);
>>
>>
>> Then to test them all:
>>
>> if ( @options = grep $word =~ /$_/, @options ) {
>>
>> print "All pattern matched!\n";
>> }
>>
>
>
> I don't understand how that grep works. Here is an example I constructed:
>
> my $word = 'ac';
> my @options = ('a', 'b', 'c');
>
> @options = grep $word =~ /$_/, @options;
>
> print "@options\n";
>
> if (@options) {print "They all matched!\n"}
>
Whoops. I forgot the output for that code:
--output:--
a c
They all matched!
> The way I understand it, if @options isn't an empty array then the if
> condition will evaluate to true. It appears to me that @options will not be
> empty if only one pattern matches the word.
>
