Symbol

        # Symbol < Object

---
# Includes:
Comparable (from ruby core)

(from ruby core)
---

Symbol objects represent named identifiers inside the Ruby interpreter.

You can create a Symbol object explicitly with:

*   A [symbol
    literal](doc/syntax/literals_rdoc.html#label-Symbol+Literals).


The same Symbol object will be created for a given name or string for
the duration of a program's execution, regardless of the context or
meaning of that name. Thus if `Fred` is a constant in one context, a
method in another, and a class in a third, the Symbol `:Fred` will be
the same object in all three contexts.

    module One
      class Fred
      end
      $f1 = :Fred
    end
    module Two
      Fred = 1
      $f2 = :Fred
    end
    def Fred()
    end
    $f3 = :Fred
    $f1.object_id   #=> 2514190
    $f2.object_id   #=> 2514190
    $f3.object_id   #=> 2514190

Constant, method, and variable names are returned as symbols:

    module One
      Two = 2
      def three; 3 end
      @four = 4
      @@five = 5
      $six = 6
    end
    seven = 7

    One.constants
    # => [:Two]
    One.instance_methods(true)
    # => [:three]
    One.instance_variables
    # => [:@four]
    One.class_variables
    # => [:@@five]
    global_variables.grep(/six/)
    # => [:$six]
    local_variables
    # => [:seven]

Symbol objects are different from String objects in that Symbol objects
represent identifiers, while String objects represent text or data.

## What's Here

First, what's elsewhere. Class Symbol:

*   Inherits from [class
    Object](Object.html#class-Object-label-What-27s+Here).
*   Includes [module
    Comparable](Comparable.html#module-Comparable-label-What-27s+Here).


Here, class Symbol provides methods that are useful for:

*   [Querying](#class-Symbol-label-Methods+for+Querying)
*   [Comparing](#class-Symbol-label-Methods+for+Comparing)
*   [Converting](#class-Symbol-label-Methods+for+Converting)


### Methods for Querying

    ::all_symbols
:       Returns an array of the symbols currently in Ruby's symbol
        table.

    [#=~](#method-i-3D~)
:       Returns the index of the first substring in symbol that matches
        a given Regexp or other object; returns `nil` if no match is
        found.

    #[], #slice
:       Returns a substring of symbol determined by a given index,
        start/length, or range, or string.

    #empty?
:       Returns `true` if `self.length` is zero; `false` otherwise.

    #encoding
:       Returns the Encoding object that represents the encoding of
        symbol.

    #end_with?
:       Returns `true` if symbol ends with any of the given strings.

    #match
:       Returns a MatchData object if symbol matches a given Regexp;
        `nil` otherwise.

    #match?
:       Returns `true` if symbol matches a given Regexp; `false`
        otherwise.

    #length, #size
:       Returns the number of characters in symbol.

    #start_with?
:       Returns `true` if symbol starts with any of the given strings.



### Methods for Comparing

    [#<=>](#method-i-3C-3D-3E)
:       Returns -1, 0, or 1 as a given symbol is smaller than, equal to,
        or larger than symbol.

    [#==, #===](#method-i-3D-3D)
:       Returns `true` if a given symbol has the same content and
        encoding.

    #casecmp
:       Ignoring case, returns -1, 0, or 1 as a given symbol is smaller
        than, equal to, or larger than symbol.

    #casecmp?
:       Returns `true` if symbol is equal to a given symbol after
        Unicode case folding; `false` otherwise.



### Methods for Converting

    #capitalize
:       Returns symbol with the first character upcased and all other
        characters downcased.

    #downcase
:       Returns symbol with all characters downcased.

    #inspect
:       Returns the string representation of `self` as a symbol literal.

    #name
:       Returns the frozen string corresponding to symbol.

    #succ, #next
:       Returns the symbol that is the successor to symbol.

    #swapcase
:       Returns symbol with all upcase characters downcased and all
        downcase characters upcased.

    #to_proc
:       Returns a Proc object which responds to the method named by
        symbol.

    #to_s, #id2name
:       Returns the string corresponding to `self`.

    #to_sym, #intern
:       Returns `self`.

    #upcase
:       Returns symbol with all characters upcased.


---
# Class methods:

    all_symbols
    json_create

# Instance methods:

    <=>
    ==
    ===
    =~
    []
    as_json
    capitalize
    casecmp
    casecmp?
    downcase
    empty?
    encoding
    end_with?
    id2name
    inspect
    intern
    length
    match
    match?
    name
    next
    size
    slice
    start_with?
    succ
    swapcase
    to_json
    to_proc
    to_s
    to_sym
    upcase

(from gem builder-3.2.4)
---
# Instance methods:

    _blankslate_as_name