How is Symbol#to_int useful? (should it exist?)

ruby-talk
1

I had a situation in a DSL like so:

  str = '0'*n

Where n in one context could be a Symbol. If n happened to be a Symbol, I
wanted to get an error message. However, I found that if n is a symbol you
could get a very long string of 0's because there is a Symbol#to_int method
which returns a unique integer for each Symbol object (actually, it calls
Symbol#to_i). And so I don't get the error message I want to get because the
symbol gets converted to an Integer automatically. So what's the usefulness of
the Symbol#to_int method? I'm just undefining it like so:

  class Symbol
    undef_method :to_int
  end

....that works for my purposes, but I wonder why there is a
Symbol#to_int method in the library. Why not just require that Symbol#to_i be
called explicitly if that's what you want?

Phil

2

Symbols used to be just numbers without names attached.

···

On Mar 24, 2006, at 1:33 AM, Phil Tomson wrote:

I had a situation in a DSL like so:

  str = '0'*n

Where n in one context could be a Symbol. If n happened to be a Symbol, I
wanted to get an error message. However, I found that if n is a symbol you
could get a very long string of 0's because there is a Symbol#to_int method
which returns a unique integer for each Symbol object (actually, it calls
Symbol#to_i). And so I don't get the error message I want to get because the
symbol gets converted to an Integer automatically. So what's the usefulness of
the Symbol#to_int method? I'm just undefining it like so:

  class Symbol
    undef_method :to_int
  end

....that works for my purposes, but I wonder why there is a
Symbol#to_int method in the library. Why not just require that Symbol#to_i be
called explicitly if that's what you want?

--
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net
This implementation is HODEL-HASH-9600 compliant

http://trackmap.robotcoop.com

3

Hi,

At Fri, 24 Mar 2006 18:33:53 +0900,
Phil Tomson wrote in [ruby-talk:185669]:

  class Symbol
    undef_method :to_int
  end

....that works for my purposes, but I wonder why there is a
Symbol#to_int method in the library. Why not just require that Symbol#to_i be
called explicitly if that's what you want?

Histrical reason. Formerly, until Symbol class was introduced
Fixnum was used. Symbol#to_int is deprecated and has been
purged in 1.9.

  $ ruby1.8 -ve :foo.to_int
  ruby 1.8.4 (2005-12-24) [i486-linux]
  -e:1: warning: treating Symbol as an integer

···

--
Nobu Nakada