Perl is awesome. Perl’s docs are awesome. The Perl community is …awesome.For those Perlers who long for elegant OO features built-in from the beginning, Ruby may be foryou.

Similarities

As with Perl, in Ruby,…

• You’ve got a package management system, somewhat like CPAN (thoughit’s calledRubyGems).
• Regexes are built right in. Bon appétit!
• There’s a fairly large number of commonly-used built-ins.
• Parentheses are often optional.
• Strings work basically the same.
• There’s a general delimited string and regex quoting syntax similar toPerl’s. It looks like%q{this} (single-quoted), or%Q{this} (double-quoted), and%w{this for a single-quoted list of words}.You%Q|can|%Q(use)%Q^other^ delimiters if you like.
• You’ve got double-quotish variable interpolation, though it"looks#{like} this" (and you can put any Ruby code you like inside that#{}).
• Shell command expansion uses`backticks`.
• You’ve got embedded doc tools (Ruby’s is called rdoc).

Differences

Unlike Perl, in Ruby,…

• You don’t have the context-dependent rules like with Perl.
• A variable isn’t the same as the object to which it refers. Instead,it’s always just a reference to an object.
• Although$ and@ are used as the first character invariable names sometimes, rather than indicating type, they indicatescope ($ for globals,@ for object instance, and@@ for class attributes).
• Array literals go in brackets instead of parentheses.
• Composing lists of other lists does not flatten them into one biglist. Instead you get an array of arrays.
• It’sdef instead ofsub.
• There’s no semicolons needed at the end of each line. Incidentally,you end things like function definitions, class definitions, and casestatements with theend keyword.
• Objects are strongly typed. You’ll be manually callingfoo.to_i,foo.to_s, etc., if you need to convert between types.
• There’s noeq,ne,lt,gt,ge, norle.
• There’s no diamond operator (<>).You usually useIO.some_method instead.
• The fat comma=> is only used for hash literals.
• There’s noundef. In Ruby you havenil.nil is an object (likeanything else in Ruby). It’s not the same as an undefined variable. Itevaluates tofalse if you treat it like a boolean.
• When tested for truth, onlyfalse andnil evaluate to a falsevalue. Everything else is true (including0,0.0, and"0").
• There’s noPerlMonks. Though the ruby-talk mailing list is a veryhelpful place.

Syndicate

Recent News (RSS)