Name
Normal Method Calls
Synopsis
obj
.method
([expr
...[, *expr
[, &expr
]]])obj
.method
[expr
...[, *expr
[, &expr
]]]obj
::method
([expr
...[, *expr
[, &expr
]]])obj
::method
[expr
...[, *expr
[, &expr
]]]
Calls a method. May take as
arguments any number of expr
followed by
*
expr
and
&
expr
. The last
expression argument can be a hash declared directly without braces.
*
expr
expands the array
value of that expression and passes it to the method.
&
expr
passes the
Proc
object value of that expression to the method
as a block. If it isn’t ambiguous, arguments need not be
enclosed in parentheses. Either .
or
::
may be used to separate the object from its
method, but it is customary in Ruby code to use ::
as the separator for class
methods.
method
([expr
...[, *expr
[, &expr
]]])method
[expr
...[, *expr
[, &expr
]]]
Calls a method of self
. This is the only form by which private methods may be called.
Within modules, module methods and private instance methods with the same name and definition are referred to by the general term module functions. This kind of method group can be called in either of the following ways:
Math.sin(1.0)
or:
include Math sin(1.0)
Tip
You can append ! or ? to the name of a Ruby method. Traditionally,
!
is appended to a method that requires more
caution than the variant of the same name without
!
. A question mark ?
is
appended to a method that determines the state of a Boolean value,
true
or false
.
Attempting to call a method without specifying either its arguments or parentheses in a context ...
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