method

to_enum

v1_9_3_125 - Show latest stable - 2 notes - Class: Object

to_enum(*args) public

Creates a new Enumerator which will enumerate by on calling method on obj.

`method`	the method to call on `obj` to generate the enumeration
`args`	arguments that will be passed in `method` in addition

to the item itself.  Note that the number of args
must not exceed the number expected by +method+

Example

str = "xyz"

enum = str.enum_for(:each_byte)
enum.each { |b| puts b }
# => 120
# => 121
# => 122

# protect an array from being modified by some_method
a = [1, 2, 3]
some_method(a.to_enum)

Show source

static VALUE
obj_to_enum(int argc, VALUE *argv, VALUE obj)
{
    VALUE meth = sym_each;

    if (argc > 0) {
        --argc;
        meth = *argv++;
    }
    return rb_enumeratorize(obj, meth, argc, argv);
}

August 23, 2008

2 thanks

Needs requiring 'enumerator' to work

This method needs that you

require 'enumerator'

for this method to be available.

July 30, 2011 - (>= v1_9_1_378)

0 thanks

now they are built-in

in ruby 1.9 and afterwards, the to_enum and enum_for(synonym for to_enum) methods are buil-in to the language. so there’s no need to require that any more.

to_enum

Related methods

Example

Needs requiring 'enumerator' to work

now they are built-in