View Source erl_id_trans (stdlib v6.0)
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/2 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.
Parse Transformations
Parse transformations are used if a programmer wants to use Erlang syntax, 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 transformations. No support is offered for problems encountered.
See Also
Summary
Functions
Performs an identity transformation on Erlang forms, as an example.
Returns information about the parse transform itself.
Functions
-spec parse_transform(Forms, Options) -> NewForms when Forms :: [erl_parse:abstract_form() | erl_parse:form_info()], NewForms :: Forms, Options :: [compile:option()].
Performs an identity transformation on Erlang forms, as an example.
-spec parse_transform_info() -> #{error_location => column | line}.
Returns information about the parse transform itself.