Ruby Programming/Syntax/Lexicology
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[edit] Identifiers
Example:
foobar ruby_is_simple
An identifier in Ruby begins with an English letter (A-Za-z) or underscore (_) and consists of alphanumeric characters (A-Za-z0-9) or underscores (_). There is no restriction to its length. Identifiers are names used to identify variables, definitions, classes, etcetera in a program and from other other variables, definitions, …. An identifier cannot have a reserved word as its name .
[edit] Comments
Example:
# this is a comment line
Other than within a string, a comment is regarded as the text from the # to the end of the line.
[edit] Embedded Documentation
Example:
=begin everything between a line beginning with `=begin' down to one beginning with `=end' will be skipped by the interpreter. =end
[edit] Reserved Words
The following words are reserved in Ruby:
=begin =end alias and begin BEGIN break case class def defined? do else elsif END end ensure false for if in module next nil not or redo rescue retry return self super then true undef unless until when while yield
[edit] Expressions
Example: true
(1 + 2) * 3 foo() if test then okay else not_good end
All variables, literals, operators, control structures, etcetera are expressions. Using these together is called a program. You can divide expressions with newlines or semicolons (;) — however, a newline with a preceeding backslash (\) is continued to the following line.
