x-perl-expand-signature-pp

#!/usr/bin/env perl


#### RE's

my $decl_re = qr/
  ^
  \s*
  (method|func)
  \s*
  ([\w_]+)
  \s*
  [(]
  (.+?)
  [)]
  \s*
  [{]
  $
/x;

my $match_self_name = qr/
  \s*
  \$
  ([\w_]+)
  :
  \s*
  ,?
  \s*
/x;

my $match_pos_protos = qr/
  \s*
  \$
  ([\w_]+)
  \s*
  (\?)?
  \s*
  ,?
  \s*
/x;

my $match_named_protos = qr/
  \s*
  :
  \$
  ([\w_]+)
  \s*
  (?:
    =
    \s*
    (
      (?:
        ["']
        .*?
        ['"]
      )
      |
      (?:
        [{\]]
        .*?
        [}\]]
      )
      |
      (?:
        [^,]*
      )
    )
    \s*
  )?
  \s*
  ,?
  \s*
/x;


#### Code

my $decl = do { local $\; <> };
my ($type, $name, $proto) = $decl =~ m/$decl_re/;
my @perl = ("sub $name {");

if ($type eq 'method') {
  if ($proto =~ s/^$match_self_name//) {
    push @perl, "  my \$$1 = shift;";
  }
  else {
    push @perl, '  my $self = shift;';
  }
}

## collect fixed pos args
my @fixed;
while ($proto =~ s/^$match_pos_protos//) {
  
}

## collect named args
my @named;
while ($proto =~ s/^$match_named_protos//) {
  push @named, { name => $1, default => $2};
}

print "# $decl\n", join("\n", @perl), "\n";
use Data::Dump qw(pp); print "proto '$proto' = ", pp(\@named), "\n";