# Re: Method parameters Type **URL:** \ **Category:** Ruby\ **Created:** [April 7, 2008, 10:30pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109 "2008-04-07T22:30:03Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 7, 2008, 10:30pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/1 "2008-04-07T22:30:03Z")
From: Sreedhar K. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > > Unlike Java why does not ruby specify the method parameter types. Because, unlike Java, Ruby is not a strongly typed language. > > How can a caller know what type of parameter is the method expecting. Read the method’s documentation? ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 7, 2008, 10:44pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/2 "2008-04-07T22:44:20Z")
On Mon, Apr 7, 2008 at 4:28 PM, Mike B. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Because, unlike Java, Ruby is not a strongly typed language. To be pedantic, both Java and Ruby are strongly typed. However, Java is statically types, and Ruby is dynamically typed. ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 7, 2008, 11:13pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/3 "2008-04-07T23:13:08Z")
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Avdi G. wrote: | On Mon, Apr 7, 2008 at 4:28 PM, Mike B. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: |\> Because, unlike Java, Ruby is not a strongly typed language. | | To be pedantic, both Java and Ruby are strongly typed. However, Java | is statically types, and Ruby is dynamically typed. | Ruby is? irb(main):001:0\> t = String.new =\> “” irb(main):002:0\> t.class =\> String irb(main):003:0\> t = 1 =\> 1 irb(main):004:0\> t.class =\> Fixnum irb(main):005:0\> exit Doesn’t look like it to me, since I can change the type of a variable with ease. * * * Phillip G. Twitter: [twitter.com/cynicalryan](http://twitter.com/cynicalryan) Rule of Open-Source Programming #37: Duplicate effort is inevitable. Live with it. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (MingW32) Comment: Using GnuPG with Mozilla - [http://enigmail.mozdev.org](http://enigmail.mozdev.org) iEYEARECAAYFAkf6jiUACgkQbtAgaoJTgL9AOgCfU5pDjiz+K1RP35cLhk9xZnlz 63AAoIKEeH+TUqC82uUoIHke3v+FpnzW =9FdL -----END PGP SIGNATURE----- ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 7, 2008, 11:28pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/4 "2008-04-07T23:28:28Z")
On Mon, Apr 7, 2008 at 5:12 PM, Phillip G. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Ruby is? > > Doesn’t look like it to me, since I can change the type of a variable > with ease. You’re confusing static typing and strong typing. In a weakly-typed language, like C, it is possible to cast an integer as a, for instance, a char\*, and then call string functions like sprintf() on it and the compiler will compile it, the runtime will run it, and it will wreak whatever havoc you please. Most high-level languages are strongly-typed, these days - neither Java or Ruby will allow you to call a String method on an Integer. You can assign whatever object you want to a variable in Ruby - hence _dynamic_ typing - but that object will only ever allow you to call supported methods on it; otherwise you’ll get a NoMethodError. Hence _strong_ typing. ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 7, 2008, 11:27pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/5 "2008-04-07T23:27:18Z")
El Lunes, 7 de Abril de 2008, Phillip G. escribió:\> > Doesn’t look like it to me, since I can change the type of a variable > with ease. No, look at the following example: irb(main):001:0\> text = "The number is: " =\> "The number is: " irb(main):002:0\> number = 25 =\> 25 irb(main):003:0\> puts text + number TypeError: can’t convert Fixnum into String from (irb):3:in `+’ from (irb):3 from :0 ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 8, 2008, 11:12pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/6 "2008-04-08T23:12:46Z")
On 08.04.2008 00:53, Phillip G. wrote: > | > | methods on it; otherwise you’ll get a NoMethodError. Hence _strong_ > | typing. > | > > Thanks for the enlightenment. 🙂 Another way to put it would be that Ruby’s variables are type-less, while objects do have a specific type. While we’re at it: type != class. Basically the type is defined by all operations (aka methods) usable on an instance - not the class it was created from. Kind regards robert ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 8, 2008, 12:53am UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/7 "2008-04-08T00:53:58Z")
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Avdi G. wrote: | On Mon, Apr 7, 2008 at 5:12 PM, Phillip G. | [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: |\> Ruby is? |\> |\> Doesn’t look like it to me, since I can change the type of a variable |\> with ease. | | You’re confusing static typing and strong typing. | | In a weakly-typed language, like C, it is possible to cast an integer | as a, for instance, a char\*, and then call string functions like | sprintf() on it and the compiler will compile it, the runtime will run | it, and it will wreak whatever havoc you please. Most high-level | languages are strongly-typed, these days - neither Java or Ruby will | allow you to call a String method on an Integer. You can assign | whatever object you want to a variable in Ruby - hence _dynamic_ | typing - but that object will only ever allow you to call supported | methods on it; otherwise you’ll get a NoMethodError. Hence _strong_ | typing. | Thanks for the enlightenment. 🙂 * * * Phillip G. Twitter: [twitter.com/cynicalryan](http://twitter.com/cynicalryan) Zmodem has bigger bits, softer blocks, and tighter ASCII. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (MingW32) Comment: Using GnuPG with Mozilla - [http://enigmail.mozdev.org](http://enigmail.mozdev.org) iEYEARECAAYFAkf6pcwACgkQbtAgaoJTgL9trwCghb7DYangJvsq/ktpceHh12FD 004AnikbmUhG0gwWUJywu43qfbPa76sK =b6S6 -----END PGP SIGNATURE----- ---
**Author:** ![asplake](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/2bfe46/32.png) [@asplake](https://www.ruby-forum.com/u/asplake)\ **Post date:** [April 8, 2008, 11:33pm UTC](https://www.ruby-forum.com/t/re-method-parameters-type/134109/8 "2008-04-08T23:33:16Z")
Avdi G. wrote: > To be pedantic, both Java and Ruby are strongly typed. However, Java > is statically types, and Ruby is dynamically typed Indeed. I stand linguistically admonished. 🙂