Prism::UnlessNode

Class

Represents the use of the ‘unless` keyword, either in the block form or the modifier form.

bar unless foo
^^^^^^^^^^^^^^

unless foo then bar end
^^^^^^^^^^^^^^^^^^^^^^^
Attributes

predicate

Read

The condition to be evaluated for the unless expression. It can be any [non-void expression](github.com/ruby/prism/blob/main/docs/parsing_rules.md#non-void-expression).

unless cond then bar end
       ^^^^

bar unless cond
           ^^^^

statements

Read

The body of statements that will executed if the unless condition is falsey. Will be ‘nil` if no body is provided.

unless cond then bar end
                 ^^^

consequent

Read

The else clause of the unless expression, if present.

unless cond then bar else baz end
                     ^^^^^^^^
Class Methods

new(source, keyword_loc, predicate, then_keyword_loc, statements, consequent, end_keyword_loc, location)
::

def initialize: (Location keyword_loc, Prism::node predicate, Location? then_keyword_loc, StatementsNode? statements, ElseNode? consequent, Location? end_keyword_loc, Location location) -> void

type
::

Similar to type, this method returns a symbol that you can use for splitting on the type of the node without having to do a long === chain. Note that like type, it will still be slower than using == for a single class, but should be faster in a case statement or an array comparison.

def self.type: () -> Symbol

Instance Methods

===(other)
#

Implements case-equality for the node. This is effectively == but without comparing the value of locations. Locations are checked only for presence.

accept(visitor)
#

def accept: (Visitor visitor) -> void

child_nodes
#

def child_nodes: () -> Array[nil | Node]

comment_targets
#

def comment_targets: () -> Array[Node | Location]

compact_child_nodes
#

def compact_child_nodes: () -> Array

copy(keyword_loc: self.keyword_loc, predicate: self.predicate, then_keyword_loc: self.then_keyword_loc, statements: self.statements, consequent: self.consequent, end_keyword_loc: self.end_keyword_loc, location: self.location)
#

def copy: (?keyword_loc: Location, ?predicate: Prism::node, ?then_keyword_loc: Location?, ?statements: StatementsNode?, ?consequent: ElseNode?, ?end_keyword_loc: Location?, ?location: Location) -> UnlessNode

deconstruct
#
An alias for child_nodes

deconstruct_keys(keys)
#

def deconstruct_keys: (Array keys) -> { keyword_loc: Location, predicate: Prism::node, then_keyword_loc: Location?, statements: StatementsNode?, consequent: ElseNode?, end_keyword_loc: Location?, location: Location }

end_keyword
#

def end_keyword: () -> String?

end_keyword_loc
#

The location of the ‘end` keyword, if present.

unless cond then bar end
                     ^^^

inspect
#

def inspect -> String

keyword
#

def keyword: () -> String

keyword_loc
#

The location of the ‘unless` keyword.

unless cond then bar end
^^^^^^

bar unless cond
    ^^^^^^

then_keyword
#

def then_keyword: () -> String?

then_keyword_loc
#

The location of the ‘then` keyword, if present. unless cond then bar end ^^^^

type
#

Sometimes you want to check an instance of a node against a list of classes to see what kind of behavior to perform. Usually this is done by calling ‘[cls1, cls2].include?(node.class)` or putting the node into a case statement and doing `case node; when cls1; when cls2; end`. Both of these approaches are relatively slow because of the constant lookups, method calls, and/or array allocations.

Instead, you can call type, which will return to you a symbol that you can use for comparison. This is faster than the other approaches because it uses a single integer comparison, but also because if you’re on CRuby you can take advantage of the fact that case statements with all symbol keys will use a jump table.

def type: () -> Symbol