# class Prism::DesugarCompiler

`DesugarCompiler` is a compiler that desugars Ruby code into a more primitive form. This is useful for consumers that want to deal with fewer node types.

### Public Instance Methods

visit_class_variable_and_write_node(node) click to toggle source

@@foo &&= bar

becomes

@@foo && @@foo = bar

    # File lib/prism/desugar_compiler.rb, line 12
    def visit_class_variable_and_write_node(node)
      desugar_and_write_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
    end

visit_class_variable_operator_write_node(node) click to toggle source

@@foo += bar

becomes

@@foo = @@foo + bar

    # File lib/prism/desugar_compiler.rb, line 30
    def visit_class_variable_operator_write_node(node)
      desugar_operator_write_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
    end

visit_class_variable_or_write_node(node) click to toggle source

@@foo ||= bar

becomes

defined?(@@foo) ? @@foo : @@foo = bar

    # File lib/prism/desugar_compiler.rb, line 21
    def visit_class_variable_or_write_node(node)
      desugar_or_write_defined_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
    end

visit_constant_and_write_node(node) click to toggle source

Foo &&= bar

becomes

Foo && Foo = bar

    # File lib/prism/desugar_compiler.rb, line 39
    def visit_constant_and_write_node(node)
      desugar_and_write_node(node, ConstantReadNode, ConstantWriteNode, node.name)
    end

visit_constant_operator_write_node(node) click to toggle source

Foo += bar

becomes

Foo = Foo + bar

    # File lib/prism/desugar_compiler.rb, line 57
    def visit_constant_operator_write_node(node)
      desugar_operator_write_node(node, ConstantReadNode, ConstantWriteNode, node.name)
    end

visit_constant_or_write_node(node) click to toggle source

Foo ||= bar

becomes

defined?(Foo) ? Foo : Foo = bar

    # File lib/prism/desugar_compiler.rb, line 48
    def visit_constant_or_write_node(node)
      desugar_or_write_defined_node(node, ConstantReadNode, ConstantWriteNode, node.name)
    end

visit_global_variable_and_write_node(node) click to toggle source

$foo &&= bar

becomes

$foo && $foo = bar

    # File lib/prism/desugar_compiler.rb, line 66
    def visit_global_variable_and_write_node(node)
      desugar_and_write_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
    end

visit_global_variable_operator_write_node(node) click to toggle source

$foo += bar

becomes

$foo = $foo + bar

    # File lib/prism/desugar_compiler.rb, line 84
    def visit_global_variable_operator_write_node(node)
      desugar_operator_write_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
    end

visit_global_variable_or_write_node(node) click to toggle source

$foo ||= bar

becomes

defined?($foo) ? $foo : $foo = bar

    # File lib/prism/desugar_compiler.rb, line 75
    def visit_global_variable_or_write_node(node)
      desugar_or_write_defined_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
    end

visit_instance_variable_and_write_node(node) click to toggle source

@foo &&= bar

becomes

@foo && @foo = bar

    # File lib/prism/desugar_compiler.rb, line 93
    def visit_instance_variable_and_write_node(node)
      desugar_and_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
    end

visit_instance_variable_operator_write_node(node) click to toggle source

@foo += bar

becomes

@foo = @foo + bar

    # File lib/prism/desugar_compiler.rb, line 111
    def visit_instance_variable_operator_write_node(node)
      desugar_operator_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
    end

visit_instance_variable_or_write_node(node) click to toggle source

@foo ||= bar

becomes

@foo || @foo = bar

    # File lib/prism/desugar_compiler.rb, line 102
    def visit_instance_variable_or_write_node(node)
      desugar_or_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
    end

visit_local_variable_and_write_node(node) click to toggle source

foo &&= bar

becomes

foo && foo = bar

    # File lib/prism/desugar_compiler.rb, line 120
    def visit_local_variable_and_write_node(node)
      desugar_and_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
    end

visit_local_variable_operator_write_node(node) click to toggle source

foo += bar

becomes

foo = foo + bar

    # File lib/prism/desugar_compiler.rb, line 138
    def visit_local_variable_operator_write_node(node)
      desugar_operator_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
    end

visit_local_variable_or_write_node(node) click to toggle source

foo ||= bar

becomes

foo || foo = bar

    # File lib/prism/desugar_compiler.rb, line 129
    def visit_local_variable_or_write_node(node)
      desugar_or_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
    end

### Private Instance Methods

desugar_and_write_node(node, read_class, write_class, *arguments) click to toggle source

Desugar ‘x &&= y` to `x && x = y`

    # File lib/prism/desugar_compiler.rb, line 145
    def desugar_and_write_node(node, read_class, write_class, *arguments)
      AndNode.new(
        read_class.new(*arguments, node.name_loc),
        write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location),
        node.operator_loc,
        node.location
      )
    end

desugar_operator_write_node(node, read_class, write_class, *arguments) click to toggle source

Desugar ‘x += y` to `x = x + y`

    # File lib/prism/desugar_compiler.rb, line 155
    def desugar_operator_write_node(node, read_class, write_class, *arguments)
      write_class.new(
        *arguments,
        node.name_loc,
        CallNode.new(
          0,
          read_class.new(*arguments, node.name_loc),
          nil,
          node.operator_loc.slice.chomp("="),
          node.operator_loc.copy(length: node.operator_loc.length - 1),
          nil,
          ArgumentsNode.new(0, [node.value], node.value.location),
          nil,
          nil,
          node.location
        ),
        node.operator_loc.copy(start_offset: node.operator_loc.end_offset - 1, length: 1),
        node.location
      )
    end

desugar_or_write_defined_node(node, read_class, write_class, *arguments) click to toggle source

Desugar ‘x ||= y` to `defined?(x) ? x : x = y`

    # File lib/prism/desugar_compiler.rb, line 187
    def desugar_or_write_defined_node(node, read_class, write_class, *arguments)
      IfNode.new(
        node.operator_loc,
        DefinedNode.new(nil, read_class.new(*arguments, node.name_loc), nil, node.operator_loc, node.name_loc),
        node.operator_loc,
        StatementsNode.new([read_class.new(*arguments, node.name_loc)], node.location),
        ElseNode.new(
          node.operator_loc,
          StatementsNode.new(
            [write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location)],
            node.location
          ),
          node.operator_loc,
          node.location
        ),
        node.operator_loc,
        node.location
      )
    end

desugar_or_write_node(node, read_class, write_class, *arguments) click to toggle source

Desugar ‘x ||= y` to `x || x = y`

    # File lib/prism/desugar_compiler.rb, line 177
    def desugar_or_write_node(node, read_class, write_class, *arguments)
      OrNode.new(
        read_class.new(*arguments, node.name_loc),
        write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location),
        node.operator_loc,
        node.location
      )
    end