Class: Opal::Nodes::RestargNode

Inherits:
Base
  • Object
show all
Defined in:
opal/lib/opal/nodes/args/restarg.rb

Overview

A node responsible for extracting a rest argument (or splat argument)

def m(*rest)

Constant Summary

Constants included from Helpers

Helpers::BASIC_IDENTIFIER_RULES, Helpers::ES3_RESERVED_WORD_EXCLUSIVE, Helpers::ES51_RESERVED_WORD, Helpers::IMMUTABLE_PROPS, Helpers::PROTO_SPECIAL_METHODS, Helpers::PROTO_SPECIAL_PROPS, Helpers::RESERVED_FUNCTION_NAMES

Instance Attribute Summary

Attributes inherited from Base

#compiler, #type

Instance Method Summary collapse

Methods inherited from Base

#add_gvar, #add_ivar, #add_local, #add_temp, #children, children, #compile_to_fragments, #error, #expr, #expr?, #expr_or_nil, #fragment, handle, handlers, #has_rescue_else?, #helper, #in_ensure, #in_ensure?, #in_while?, #initialize, #process, #push, #recv, #recv?, #s, #scope, #stmt, #stmt?, truthy_optimize?, #unshift, #while_loop, #with_temp, #wrap

Methods included from Helpers

#current_indent, #empty_line, #indent, #ivar, #js_falsy, #js_truthy, #js_truthy_optimize, #line, #lvar_to_js, #mid_to_jsid, #property, #valid_ivar_name?, #valid_name?, #variable

Constructor Details

This class inherits a constructor from Opal::Nodes::Base

Instance Method Details

#compileObject


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# File 'opal/lib/opal/nodes/args/restarg.rb', line 13

def compile
  restarg_name = @sexp[1]
  return unless restarg_name
  var_name = variable(restarg_name.to_sym)

  add_temp var_name

  if @sexp.meta[:post]
    # post restarg case (in mlhs or in deoptimized arguments)
    # splat is always the last item in scope.working_arguments
    line "#{var_name} = #{scope.working_arguments};"
  else
    # inline restarg case
    offset = @sexp.meta[:offset]
    # restarg value should be taken directly from parameters
    line "var $args_len = arguments.length, $rest_len = $args_len - #{offset};"
    line "if ($rest_len < 0) { $rest_len = 0; }"
    line "#{var_name} = new Array($rest_len);"
    line "for (var $arg_idx = #{offset}; $arg_idx < $args_len; $arg_idx++) {"
    line "  #{var_name}[$arg_idx - #{offset}] = arguments[$arg_idx];"
    line "}"
  end
end