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Module¶

A Fortran module or submodule.

Declaration¶

Syntax¶

Module(symbol_table symtab, identifier name, identifier? parent_module,
    identifier* dependencies, bool loaded_from_mod, bool intrinsic,
    bool has_submodules, location start_name, location end_name)

Arguments¶

Argument	Description
`symtab`	the symbol table of the module, owning everything the module declares.
`name`	the name of the module.
`parent_module`	for a submodule, the name of the module it extends; `nil` for a module.
`dependencies`	the names of the modules this module uses.
`loaded_from_mod`	`true` when the module was read back from a module file rather than compiled from source in this run.
`intrinsic`	`true` for a module defined by the language itself (`iso_c_binding`, `iso_fortran_env`, …). The backends do not emit code for it.
`has_submodules`	`true` when at least one submodule extends this module. A module procedure declared here may then be defined elsewhere.
`start_name`	the source span of the name in `module name`.
`end_name`	the source span of the name in `end module name`.

Return values¶

None.

Description¶

A Module owns the symbols it declares. Code in another program unit never looks a module symbol up through this table directly: it declares an ExternalSymbol in its own scope that points at the symbol here.

When a module is compiled, the full ASR (abi=Source, non-empty procedure bodies) and the interface ASR (abi=LFortranModule, empty bodies) are both written to the module file. loaded_from_mod records which side of that a particular Module came from.

Examples¶

(Module
  :symtab (SymbolTable
    :id 1
    :symbols {
      "pi" (Variable
        :parent_symtab 1
        :name "pi"
        :dependencies []
        :intent :Local
        :symbolic_value (RealConstant
          :r 3.1415926535897931
          :type (Real
            :kind 8
          )
        )
        :value (RealConstant
          :r 3.1415926535897931
          :type (Real
            :kind 8
          )
        )
        :storage :Parameter
        :type (Real
          :kind 8
        )
        :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 "constants"
  :parent_module nil
  :dependencies []
  :loaded_from_mod false
  :intrinsic false
  :has_submodules false
)

It comes from this complete ASR text document:

(TranslationUnit
  :symtab (SymbolTable
    :id 0
    :symbols {
      "constants" (Module
        :symtab (SymbolTable
          :id 1
          :symbols {
            "pi" (Variable
              :parent_symtab 1
              :name "pi"
              :dependencies []
              :intent :Local
              :symbolic_value (RealConstant
                :r 3.1415926535897931
                :type (Real
                  :kind 8
                )
              )
              :value (RealConstant
                :r 3.1415926535897931
                :type (Real
                  :kind 8
                )
              )
              :storage :Parameter
              :type (Real
                :kind 8
              )
              :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 "constants"
        :parent_module nil
        :dependencies []
        :loaded_from_mod false
        :intrinsic false
        :has_submodules false
      )
      "main" (Program
        :symtab (SymbolTable
          :id 2
          :symbols {}
        )
        :name "main"
        :dependencies []
        :body []
      )
    }
  )
  :items []
)

See Also¶

Program, Function, ExternalSymbol, Variable