in reply to Re^2: Dynamically constructed function calls
in thread Dynamically constructed function calls

I've toyed with the idea of making $object->do {expression-yielding-method-name} work. Right now it gives a syntax error.

Of course, you can do something pretty close by just having a do method: 

sub foo { print "in foo" }
sub do {
   my $self = shift;
   my $meth = shift;
   $self->$meth(@_)
}

$object->do("foo", @args);

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Re^4: Dynamically constructed function calls
by dragonchild (Archbishop) on Nov 04, 2004 at 04:03 UTC
    It would have to be something that has scalar context applied to it. That would yield some neat obfu. 
    package Foo;

sub new { bless {}, shift }

*$_ = sub { my ($self, $arg) = @_; print "I am $_ $arg.\n" } for 1 .. 
+5;

package main;

my $foo = Foo->new;

$foo->do { @ARGV }( 'world' );

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    Blammo! :-)

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      *$_ = sub ... doesn't work if $_ is an integer.

      $_ isn't a lexical, so it doesn't get captured, producing "I am world" for output.

      What's after the -> has to start with a $, so do { @ARGV } wouldn't work even if it did return a scalar.

      The following works

      package Foo;

sub new { bless {}, shift }

do { my $n=$_; *${\"n$n"} =
sub { my ($self, $arg) = @_; print "I am $n $arg.\n" } }
for (-1..5);

package main;

my $foo = Foo->new;

$foo->${\(n.@ARGV)}( 'world' );

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        *$_ = sub ... doesn't work if $_ is an integer.
        Not true. Did you try it? 
        $ perl -we'*$_ = sub { print "I am 1 $_[1].\n" } for 1; $x = bless {};
+ $meth = "1"; $x->$meth("world")'
I am 1 world.

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        $_ isn't a lexical, so it doesn't get captured, producing "I am world" for output.
        Correct.
        What's after the -> has to start with a $, so do { @ARGV } wouldn't work even if it did return a scalar.
        dragonchild was responding to my suggestion that ->do{} be made to work.
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