class Prism::IfNode - Documentation for Ruby 3.3

# class Prism::IfNode

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

    bar if foo
    ^^^^^^^^^^

    if foo then bar end
    ^^^^^^^^^^^^^^^^^^^

### Attributes

consequent[R]

attr_reader consequent: `Node`?

end_keyword_loc[R]

attr_reader `end_keyword_loc`: `Location`?

if_keyword_loc[R]

attr_reader `if_keyword_loc`: `Location`?

predicate[R]

attr_reader predicate: `Node`

statements[R]

attr_reader statements: `StatementsNode`?

then_keyword_loc[R]

attr_reader `then_keyword_loc`: `Location`?

### Public Class Methods

new(if_keyword_loc, predicate, then_keyword_loc, statements, consequent, end_keyword_loc, location) click to toggle source

def initialize: (`if_keyword_loc`: `Location`?, predicate: `Node`, `then_keyword_loc`: `Location`?, statements: `StatementsNode`?, consequent: `Node`?, `end_keyword_loc`: `Location`?, location: `Location`) -> void

    # File lib/prism/node.rb, line 7733
    def initialize(if_keyword_loc, predicate, then_keyword_loc, statements, consequent, end_keyword_loc, location)
      @if_keyword_loc = if_keyword_loc
      @predicate = predicate
      @then_keyword_loc = then_keyword_loc
      @statements = statements
      @consequent = consequent
      @end_keyword_loc = end_keyword_loc
      @location = location
    end

type() click to toggle source

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`

    # File lib/prism/node.rb, line 7854
    def self.type
      :if_node
    end

### Public Instance Methods

accept(visitor) click to toggle source

def accept: (visitor: `Visitor`) -> void

    # File lib/prism/node.rb, line 7744
    def accept(visitor)
      visitor.visit_if_node(self)
    end

child_nodes() click to toggle source

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

    # File lib/prism/node.rb, line 7753
    def child_nodes
      [predicate, statements, consequent]
    end

Also aliased as: deconstruct
comment_targets() click to toggle source

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

    # File lib/prism/node.rb, line 7767
    def comment_targets
      [*if_keyword_loc, predicate, *then_keyword_loc, *statements, *consequent, *end_keyword_loc]
    end

compact_child_nodes() click to toggle source

def `compact_child_nodes`: () -> Array

    # File lib/prism/node.rb, line 7758
    def compact_child_nodes
      compact = []
      compact << predicate
      compact << statements if statements
      compact << consequent if consequent
      compact
    end

copy(**params) click to toggle source

def copy: (**params) -> `IfNode`

    # File lib/prism/node.rb, line 7772
    def copy(**params)
      IfNode.new(
        params.fetch(:if_keyword_loc) { if_keyword_loc },
        params.fetch(:predicate) { predicate },
        params.fetch(:then_keyword_loc) { then_keyword_loc },
        params.fetch(:statements) { statements },
        params.fetch(:consequent) { consequent },
        params.fetch(:end_keyword_loc) { end_keyword_loc },
        params.fetch(:location) { location },
      )
    end

deconstruct()

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

Alias for: child_nodes
deconstruct_keys(keys) click to toggle source

def `deconstruct_keys`: (keys: Array) -> Hash[Symbol, nil | `Node` | Array | `String` | `Token` | Array | Location]

    # File lib/prism/node.rb, line 7788
    def deconstruct_keys(keys)
      { if_keyword_loc: if_keyword_loc, predicate: predicate, then_keyword_loc: then_keyword_loc, statements: statements, consequent: consequent, end_keyword_loc: end_keyword_loc, location: location }
    end

end_keyword() click to toggle source

def `end_keyword`: () -> `String`?

    # File lib/prism/node.rb, line 7803
    def end_keyword
      end_keyword_loc&.slice
    end

if_keyword() click to toggle source

def `if_keyword`: () -> `String`?

    # File lib/prism/node.rb, line 7793
    def if_keyword
      if_keyword_loc&.slice
    end

inspect(inspector = NodeInspector.new) click to toggle source

def inspect(inspector: NodeInspector) -> `String`

    # File lib/prism/node.rb, line 7808
    def inspect(inspector = NodeInspector.new)
      inspector << inspector.header(self)
      inspector << "├── if_keyword_loc: #{inspector.location(if_keyword_loc)}\n"
      inspector << "├── predicate:\n"
      inspector << inspector.child_node(predicate, "│   ")
      inspector << "├── then_keyword_loc: #{inspector.location(then_keyword_loc)}\n"
      if (statements = self.statements).nil?
        inspector << "├── statements: ∅\n"
      else
        inspector << "├── statements:\n"
        inspector << statements.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
      end
      if (consequent = self.consequent).nil?
        inspector << "├── consequent: ∅\n"
      else
        inspector << "├── consequent:\n"
        inspector << consequent.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
      end
      inspector << "└── end_keyword_loc: #{inspector.location(end_keyword_loc)}\n"
      inspector.to_str
    end

then_keyword() click to toggle source

def `then_keyword`: () -> `String`?

    # File lib/prism/node.rb, line 7798
    def then_keyword
      then_keyword_loc&.slice
    end

type() click to toggle source

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`

    # File lib/prism/node.rb, line 7844
    def type
      :if_node
    end