FunctionParam

A reference to a dummy argument from inside a signature.

Declaration

Syntax

FunctionParam(int param_number, ttype type, expr? value)

Arguments

Argument	Description
param_number	the position of the argument, counting from zero.
type	the type of the expression.
value	the compile time value of the expression, when the frontend could fold it; nil otherwise.

Return values

The value of the expression.

Description

The declaration real :: a(n) in a procedure whose first dummy argument is n gives the array a bound that depends on another argument. In the FunctionType there are no symbols to point at, so the bound refers to the argument by position instead, with a FunctionParam.

It is only meaningful inside a signature. In the body of the procedure the same value is an ordinary Var.

Examples

(FunctionParam
  :param_number 0
  :type (Integer
    :kind 4
  )
  :value nil
)

It comes from this complete ASR text document:

(TranslationUnit
  :symtab (SymbolTable
    :id 0
    :symbols {
      "m" (Module
        :symtab (SymbolTable
          :id 1
          :symbols {
            "fill" (Function
              :symtab (SymbolTable
                :id 2
                :symbols {
                  "a" (Variable
                    :parent_symtab 2
                    :name "a"
                    :dependencies []
                    :intent :Out
                    :symbolic_value nil
                    :value nil
                    :storage :Default
                    :type (Array
                      :type (Real
                        :kind 4
                      )
                      :dims [
                        (dimension
                          :start (IntegerConstant
                            :n 1
                            :type (Integer
                              :kind 4
                            )
                            :intboz_type :Decimal
                          )
                          :length (FunctionParam
                            :param_number 0
                            :type (Integer
                              :kind 4
                            )
                            :value nil
                          )
                        )
                      ]
                      :physical_type :PointerArray
                    )
                    :type_declaration nil
                    :abi :Source
                    :access :Public
                    :presence :Required
                    :value_attr false
                    :target_attr false
                    :contiguous_attr false
                    :bindc_name nil
                    :is_volatile false
                    :is_protected false
                    :pass_attr :NotMethod
                    :self_argument nil
                    :codims []
                  )
                  "n" (Variable
                    :parent_symtab 2
                    :name "n"
                    :dependencies []
                    :intent :In
                    :symbolic_value nil
                    :value nil
                    :storage :Default
                    :type (Integer
                      :kind 4
                    )
                    :type_declaration nil
                    :abi :Source
                    :access :Public
                    :presence :Required
                    :value_attr false
                    :target_attr false
                    :contiguous_attr false
                    :bindc_name nil
                    :is_volatile false
                    :is_protected false
                    :pass_attr :NotMethod
                    :self_argument nil
                    :codims []
                  )
                }
              )
              :name "fill"
              :function_signature (FunctionType
                :arg_types [
                  (Integer
                    :kind 4
                  )
                  (Array
                    :type (Real
                      :kind 4
                    )
                    :dims [
                      (dimension
                        :start (IntegerConstant
                          :n 1
                          :type (Integer
                            :kind 4
                          )
                          :intboz_type :Decimal
                        )
                        :length (FunctionParam
                          :param_number 0
                          :type (Integer
                            :kind 4
                          )
                          :value nil
                        )
                      )
                    ]
                    :physical_type :PointerArray
                  )
                ]
                :return_var_type nil
                :abi :Source
                :deftype :Implementation
                :bindc_name nil
                :elemental false
                :pure false
                :module false
                :inline false
                :static false
                :restrictions []
                :is_restriction false
              )
              :dependencies []
              :args [
                (Var
                  :v (SymbolRef 2 "n")
                )
                (Var
                  :v (SymbolRef 2 "a")
                )
              ]
              :body []
              :return_var nil
              :access :Public
              :deterministic false
              :side_effect_free false
              :module_file nil
            )
          }
        )
        :name "m"
        :parent_module nil
        :dependencies []
        :loaded_from_mod false
        :intrinsic false
        :has_submodules false
      )
      "main" (Program
        :symtab (SymbolTable
          :id 3
          :symbols {}
        )
        :name "main"
        :dependencies []
        :body []
      )
    }
  )
  :items []
)

See Also

FunctionType, Function, Var