erl_id_trans - An identity parse transform.
Please see following description for synopsis
erl_id_trans(3) Erlang Module Definition erl_id_trans(3)
NAME
erl_id_trans - An identity parse transform.
DESCRIPTION
This module performs an identity parse transformation of Erlang code.
It is included as an example for users who wants to write their own
parse transformers. If option {parse_transform,Module} is passed to the
compiler, a user-written function parse_transform/2 is called by the
compiler before the code is checked for errors.
Before the function parse_transform is called, the Erlang Compiler
checks if the parse transformation can handle abstract code with column
numbers: If the function parse_transform_info/0 is implemented and
returns a map where the key error_location is associated with the value
line, the compiler removes column numbers from the abstract code before
calling the parse transform. Otherwise, the compiler passes the
abstract code on without modification.
EXPORTS
parse_transform(Forms, Options) -> Forms
Types:
Forms = [erl_parse:abstract_form() | erl_parse:form_info()]
Options = [compile:option()]
Performs an identity transformation on Erlang forms, as an exam-
ple.
parse_transform_info() -> Info
Types:
Info = #{'error_location' => 'column' | 'line'}
Returns information about the parse transform itself.
PARSE TRANSFORMATIONS
Parse transformations are used if a programmer wants to use Erlang syn-
tax, but with different semantics. The original Erlang code is then
transformed into other Erlang code.
Note:
Programmers are strongly advised not to engage in parse transforma-
tions. No support is offered for problems encountered.
SEE ALSO
erl_parse(3), compile(3)
Ericsson AB stdlib 3.17 erl_id_trans(3)