mirror of
https://github.com/idris-lang/Idris2.git
synced 2024-12-18 00:31:57 +03:00
82 lines
2.5 KiB
ReStructuredText
82 lines
2.5 KiB
ReStructuredText
**********************************
|
|
Building Idris 2 with new backends
|
|
**********************************
|
|
|
|
The way to extend Idris 2 with new backends is to use it as
|
|
a library. The module ``Idris.Driver`` exports the function
|
|
``mainWithCodegens``, that takes a list of ``(String, Codegen)``,
|
|
starting idris with these codegens in addition to the built-in ones. The first
|
|
codegen in the list will be set as the default codegen.
|
|
|
|
Getting started
|
|
===============
|
|
|
|
To use Idris 2 as a library you need a self-hosting installation and
|
|
then install the `idris2api` library (at the top level of the Idris2 repo)
|
|
|
|
::
|
|
|
|
make install-api
|
|
|
|
Now create a file containing
|
|
|
|
.. code-block:: idris
|
|
|
|
module Main
|
|
|
|
import Core.Context
|
|
import Compiler.Common
|
|
import Idris.Driver
|
|
|
|
compile : Ref Ctxt Defs -> (tmpDir : String) -> (outputDir : String) ->
|
|
ClosedTerm -> (outfile : String) -> Core (Maybe String)
|
|
compile defs tmpDir outputDir term file = do coreLift $ putStrLn "I'd rather not."
|
|
pure $ Nothing
|
|
|
|
execute : Ref Ctxt Defs -> (tmpDir : String) -> ClosedTerm -> Core ()
|
|
execute defs tmpDir term = do coreLift $ putStrLn "Maybe in an hour."
|
|
|
|
lazyCodegen : Codegen
|
|
lazyCodegen = MkCG compile execute
|
|
|
|
main : IO ()
|
|
main = mainWithCodegens [("lazy", lazyCodegen)]
|
|
|
|
Build it with
|
|
|
|
::
|
|
|
|
$ idris2 -p idris2 -p contrib -p network Lazy.idr -o lazy-idris2
|
|
|
|
Now you have an idris2 with an added backend.
|
|
|
|
::
|
|
|
|
$ ./build/exec/lazy-idris2
|
|
____ __ _ ___
|
|
/ _/___/ /____(_)____ |__ \
|
|
/ // __ / ___/ / ___/ __/ / Version 0.2.0-bd9498c00
|
|
_/ // /_/ / / / (__ ) / __/ https://www.idris-lang.org
|
|
/___/\__,_/_/ /_/____/ /____/ Type :? for help
|
|
|
|
Welcome to Idris 2. Enjoy yourself!
|
|
With codegen for: lazy
|
|
Main>
|
|
|
|
It will not be overly eager to actually compile any code with the new backend though
|
|
|
|
::
|
|
|
|
$ ./build/exec/lazy-idris2 --cg lazy Hello.idr -o hello
|
|
I'd rather not.
|
|
$
|
|
|
|
About the directories
|
|
---------------------
|
|
|
|
The code generator can assume that both ``tmpDir`` and ``outputDir`` exist. ``tmpDir``
|
|
is intended for temporary files, while ``outputDir`` is the location to put the desired
|
|
output files. By default, ``tmpDir`` and ``outputDir`` point to the same directory
|
|
(``build/exec``). The directories can be set from the package description (See Section
|
|
:ref:`ref-sect-packages`) or via command line options (Listed in ``idris2 --help``).
|