Spec entity
Spec entities correspond to -spec attributes in erlang sources. The specification for a given function is commonly present in the module where the function is defined, but it can also be placed in header files or other modules. A function might have more than one specification even if it consists of only one clause. Please note that in our representation, there is no "1:1" correlation between function clauses and -spec attributes, so any given function clause has all specs of the entire function.
Initial selector
A -spec attribute can be indicated by a given position. In this case the @spec initial-selector returns the spec entity corresponding to the indicated attribute in the source.
Selectors
The type of the result elements are indicated in parenthesis.
- function (function): The function that has this spec.
- file (file): The file in which the spec was defined.
- refmod (file): The file to which the spec pertains. (If a module identifier has been used in the spec, the result may differ from the defining file.)
- returntype (type): Possible return types of the spec.
- guardtype (type): Types of the spec-guards.
- arguments (specparam): Arguments of the spec.
Properties
The following properties are defined for spec entities:
- name (atom): Name of the function spec.
- arity (int): Arity of the spec.
- text (string): String representation of the spec.
- returntext (string): String representation of the spec's return values.
- guardtext (string): String representation of the spec's guards.
Textual output format
When using any of our interfaces, other than ris?, this entity will be represented in the output as a string with the same format as it was defined in the source file.
ri:q("mods.spec"). a.erl -spec io_lib:format(Format :: atom() | string() | binary(), D) -> [char] when D :: list(term()). ...
Review of non-trivial selectors
For some of the selectors it may not be initially clear how and what would they return. A description of these can be found here:
Spec.refmod:
Specs can have module-identifiers which determine the module whose function is being specified. This module is returned by the selector unless the module-identifier was omitted, in which case the defining module is returned.
ri:q("mods.spec.refmod"). -spec io_lib:format(Format :: atom() | string() | binary(), D) -> [char] when D :: list(term()). io_lib ...
Spec.arguments:
Returns the type expression for the arguments of the specification. Argument-names are included.
ri:q("mods.spec.args"). -spec io_lib:format(Format :: atom() | string() | binary(), D) -> [char] when D :: list(term()). Format :: atom() | string() | binary() D ...
Spec.guardtypes:
Returns the type expressions of spec-guards.
ri:q("mods.spec.guardtypes"). -spec io_lib:format(Format :: atom() | string() | binary(), D) -> [char] when D :: list(term()). D :: list(term()) ...