Re: Test not working so well

On 12/10/23 19:52, Kevin Pye wrote:
> 
> 
> On Mon, 11 Dec 2023, at 09:24, ToddAndMargo via perl6-users wrote:
>> On 12/10/23 14:16, Kevin Pye wrote:
> 
>>> Because you asked for a match with a string consisting entirely of exactly 8 digits.
> 
>> I am not following.  :'(
> 
> ^    beginning of string
> 
> <[0..9]> a digit

What do you mean "a digit".  This is not the index of the string?

I though I was testing for the characters "0" (char 48)
through "9" (char 57), not the numbers 0 through 9.


> ** 8 repeated exactly eight times
> 
> % end of string

What does the $ mean
> 
> so /^ <[0..9]> ** 8 $/ means exactly eight digits in the string, and nothing else. You have eight characters, but seven of them aren't digits, so the match fails.
> 
> Similarly in the second case.

Slowly getting there.



The Perl5 guys had a way of explaining functions that
really worked for me.  You are using the technique, so I
will give it a try and you tell me what I am doing wrong:

my Str $x="abc3defg";
if $x.match( / ^ <[0..9]> ** 8 $ / ) {
    print "True\n"; } else { print "False\n" };
False


$x is the string to test

`.match()` is the test command (method) applied to $x

the beginning and ending `/` are the constraints of the test

`^` means to start testing at the beginning of $x

`$` means to stop testing at the end of $x

`<[0..9]>` are the range of alpha numeric characters
(not numbers) to test for in  $x

`** 8` means to the test each index of $x advancing one at a
time up to  eight times.  Each index of $x is tested for
the existence of <[0..9]>.  The `8` is not the number of
characters in $x.




I am sure I got half of it wrong.

Thank you for the help!
-T




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