ImpliedDoLoop

A loop that contributes several values to an array constructor or I/O list.

Declaration

Syntax

ImpliedDoLoop(expr* values, expr var, expr start, expr end,
    expr? increment, ttype type, expr? value)

Arguments

Argument	Description
values	the expressions produced for each iteration.
var	the loop variable.
start	the first value of the loop variable.
end	the last value.
increment	the step, or nil for one.
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

(i, i=1,3) inside an array constructor, or inside the input or output list of an I/O statement. It is an expression rather than a statement because it appears where values are expected and produces a sequence of them.

The loop variable is local to the construct: it exists only while the values are being produced.

Examples

(ImpliedDoLoop
  :values [
    (Var
      :v (SymbolRef 1 "i")
    )
  ]
  :var (Var
    :v (SymbolRef 1 "i")
  )
  :start (IntegerConstant
    :n 1
    :type (Integer
      :kind 4
    )
    :intboz_type :Decimal
  )
  :end (IntegerConstant
    :n 3
    :type (Integer
      :kind 4
    )
    :intboz_type :Decimal
  )
  :increment nil
  :type (Integer
    :kind 4
  )
  :value nil
)

It comes from this complete ASR text document:

(TranslationUnit
  :symtab (SymbolTable
    :id 0
    :symbols {
      "main" (Program
        :symtab (SymbolTable
          :id 1
          :symbols {
            "a" (Variable
              :parent_symtab 1
              :name "a"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Array
                :type (Integer
                  :kind 4
                )
                :dims [
                  (dimension
                    :start (IntegerConstant
                      :n 1
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                    :length (IntegerConstant
                      :n 3
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                  )
                ]
                :physical_type :FixedSizeArray
              )
              :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 []
            )
            "i" (Variable
              :parent_symtab 1
              :name "i"
              :dependencies []
              :intent :Local
              :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 "main"
        :dependencies []
        :body [
          (Assignment
            :target (Var
              :v (SymbolRef 1 "a")
            )
            :value (ArrayConstructor
              :args [
                (ImpliedDoLoop
                  :values [
                    (Var
                      :v (SymbolRef 1 "i")
                    )
                  ]
                  :var (Var
                    :v (SymbolRef 1 "i")
                  )
                  :start (IntegerConstant
                    :n 1
                    :type (Integer
                      :kind 4
                    )
                    :intboz_type :Decimal
                  )
                  :end (IntegerConstant
                    :n 3
                    :type (Integer
                      :kind 4
                    )
                    :intboz_type :Decimal
                  )
                  :increment nil
                  :type (Integer
                    :kind 4
                  )
                  :value nil
                )
              ]
              :type (Array
                :type (Integer
                  :kind 4
                )
                :dims [
                  (dimension
                    :start (IntegerConstant
                      :n 1
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                    :length (IntegerConstant
                      :n 3
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                  )
                ]
                :physical_type :FixedSizeArray
              )
              :value nil
              :storage_format :ColMajor
              :struct_var nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
        ]
      )
    }
  )
  :items []
)

See Also

ArrayConstructor, FileWrite, DoLoop