[Dancer-users] Routes with captures

[Marc Chantreux]

hello,

> - r() already supports full regex patterns (perhaps without special extras such
> as "/x" but that can be, I believe, patched.)

it does! i wrote 

any [qw| post get |]
, r( qr(
    / ([^/]+) # the class
    / ([^/]+) # the object
    / ([^/]+) # the action
    /?$
)x ) 
, sub { "Yeah" }

and it worked! and then i was confused because the r() became useless
noise. 

> r('/.+/\w+_\w/');
> is easier and more readable than:
> qr/\/.+\/\w+_\w\//;
> 
> It's true - however - that we could try and encourage a bit more readable regex
> patters:
> qr{/.+/\w+_\w/}
> Still, readability suffers.

qr(/.+/\w+_\w/);
r('/.+/\w+_\w/');

Both are readable for me.

> However, there are certain benefits to discuss and perhaps we'll add your
> patched. Since it's not something so trivial, a discussion will ensue. :)

Ok so i try to sell my point of view :)

* r('') is code to maintain :-) 
* i really agreed your concern about readability but i don't understand
  why qr() is harder to read than r(''). I think qr() could be more
  readable in large applications:

  r('') does not use /x for the moment. as /x is a very good practice that
  is:
  - recommended in the "Perl Best Practice"
  - defaut behavior in perl6
  - very addictive for those whom still use it

  so i think

  qr(
      / ( borrower | book | shelf ) # Bizness objects 
      / ( delete | create )         # Crud actions
      / ( \d+ )                     # id 
  )

  is way easier to maintain than

  r('/(borrower|book|shelf)/(delete|create)/(\d+)')

About the feature proposed in my former message: 

qr(
  / (?<class> borrower | book | shelf ) # Bizness objects 
  / (?<action> delete | create )        # Crud actions
  / (?<id> \d+ )                        # id 
) , sub { splat->{capture}->{action} }

In the current Dancer behavior, you'll write 

'/:class/:action/:id'

seems easier but: 

- you have to test all the captures in the code, which i think is a big
  readability issue:

  unless ( my ( $action = splat->{action} )  ~~ [qw/ delete create/] ) {
    not_found("$action isn't a valid action");
  }

- you'll match tons of urls too soon so it could be very hard to write
  smart dispatcher. for exemple, i think '/:class/:action/:id' can't be
  splitted in 2 rules like this

  get qr(
    / (?<class> program | library )
    / (?<action> test | make ) 
    / (?<id> \d+ )
  )x, sub { "rule 1" };

  get qr(
    / (?<class> documentation | tickets )
    / (?<action> publish | alert ) 
    / (?<id> \d+ )
  )x, sub { "rule 2" }

Finally, and even i prefer the qr() approach, i don't see why both
syntaxes  can't cohabitate in Dancer.  

regards, 
marc