Add shebangs and x bit to executables

With run.sh, we can build and run the file in one go. This means we can also use
it as an interpreter in a shebang line and properly use the Unix executable bit.
This is pretty cool and gives a few advantages: running any executable file is
just `exec file.hs` or even `./file.hs`, finding all executables is `fd -t x`,
you don't need to specify or know an `out` name to run something, execution of a
program is standardized.

There is a hack to get this to work. In C and Common Lisp, `#!` is illegal
syntax, so I had to use shell syntax to invoke run.sh, call it on the current
file, and then exit the shell script. Meanwhile, run.sh takes the file and evals
the whole thing, building and running it. As long as either `//` or `;` is a
comment character in the target language, then this works. Maybe a better thing
to do would be to pre-process the file and remove the `#!` before passing it to
the C compiler, like [ryanmjacobs/c][1] and [tcc][2]? However this won't work in
Lisp because then I can't just load the file directly into the repl, so maybe
the comment hack needs to stay.

[1]: https://github.com/ryanmjacobs/c/tree/master
[2]: https://repo.or.cz/tinycc.git/blob/HEAD:/tccrun.c

8 files changed, 23 insertions, 24 deletions

diff --git a/Omni/Bild/Builder.nix b/Omni/Bild/Builder.nix
index a78f311..b4e6780 100644
--- a/Omni/Bild/Builder.nix
+++ b/Omni/Bild/Builder.nix
@@ -124,7 +124,12 @@ let
             . ${commonBash}
             cp ${../../pyproject.toml} ./pyproject.toml
             check ruff format --exclude 'setup.py' --check .
-            check ruff check --exclude 'setup.py' --exclude '__init__.py' .
+            # ignore EXE here to support run.sh shebangs
+            check ruff check \
+              --ignore EXE \
+              --exclude 'setup.py' \
+              --exclude '__init__.py' \
+              .
             touch ./py.typed
             check python -m mypy \
               --explicit-package-bases \
diff --git a/Omni/Bild/Deps.hs b/Omni/Bild/Deps.hs
index c2fe53f..7183c26 100644..100755
--- a/Omni/Bild/Deps.hs
+++ b/Omni/Bild/Deps.hs
@@ -1,3 +1,4 @@
+#!/usr/bin/env run.sh
 {-# LANGUAGE DerivingStrategies #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE LambdaCase #-}
diff --git a/Omni/Bild/Example.c b/Omni/Bild/Example.c
index 2f4bfd4..49b93f8 100644..100755
--- a/Omni/Bild/Example.c
+++ b/Omni/Bild/Example.c
@@ -1,3 +1,4 @@
+//usr/bin/env run.sh $0; exit
 // : out examplesodium.exe
 // : dep libsodium
 // : arg -lsodium
diff --git a/Omni/Bild/Example.hs b/Omni/Bild/Example.hs
index 025391c..3c7c144 100644..100755
--- a/Omni/Bild/Example.hs
+++ b/Omni/Bild/Example.hs
@@ -1,3 +1,4 @@
+#!/usr/bin/env run.sh
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 
diff --git a/Omni/Bild/Example.lisp b/Omni/Bild/Example.lisp
index cdabe7c..1063047 100644..100755
--- a/Omni/Bild/Example.lisp
+++ b/Omni/Bild/Example.lisp
@@ -1,3 +1,4 @@
+;/usr/bin/env run.sh $0; exit
 ;; : out helloworld.exe
 (require 'alexandria)
 (defun main ()
diff --git a/Omni/Bild/Example.py b/Omni/Bild/Example.py
index e5766ba..462a497 100644..100755
--- a/Omni/Bild/Example.py
+++ b/Omni/Bild/Example.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env run.sh
 """
 Test that bild can build Python stuff.
 
diff --git a/Omni/Bild/Example.rs b/Omni/Bild/Example.rs
index ba98dda..d6d738b 100644..100755
--- a/Omni/Bild/Example.rs
+++ b/Omni/Bild/Example.rs
@@ -1,3 +1,4 @@
+#!/usr/bin/env run.sh
 // : out helloworld
 fn main() {
   println!("Hello world!");
diff --git a/Omni/Bild/Meta.hs b/Omni/Bild/Meta.hs
index 44bcff0..a5f722e 100644
--- a/Omni/Bild/Meta.hs
+++ b/Omni/Bild/Meta.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 
@@ -6,7 +5,6 @@
 module Omni.Bild.Meta where
 
 import Alpha
-import qualified Data.Aeson as Aeson
 import qualified Data.Char as Char
 import qualified Data.Set as Set
 import qualified Data.Text as Text
@@ -29,15 +27,7 @@ type Run = String
 -- command. Should be used sparingly, and not all builds will support this.
 type Arg = String
 
-data Out = Lib String | Bin String | None
-  deriving (Show, Eq)
-
-instance Aeson.ToJSON Out where
-  toJSON =
-    Aeson.String <. Text.pack <. \case
-      Bin a -> a
-      Lib a -> a
-      None -> ""
+type Out = Maybe String
 
 data Parsed = Parsed
   { pdep :: Set Dep,
@@ -56,19 +46,24 @@ detect m cl =
     |> Set.fromList
 
 -- | 'Out' is always singular, so it gets a special function
-detectOut :: Regex.RE Char Out -> [Text] -> Out
+detectOut :: Regex.RE Char String -> [Text] -> Out
 detectOut m cl =
   cl
     /> Text.unpack
     /> Regex.match m
     |> catMaybes
     |> head
-    |> fromMaybe None
 
-detectAll :: [Char] -> [Text] -> Parsed
+-- | Detect all metadata
+detectAll ::
+  -- | The comment character(s) to match on
+  [Char] ->
+  -- | Lines of text to parse
+  [Text] ->
+  Parsed
 detectAll m cl = Parsed {..}
   where
-    pout = detectOut (out m <|> lib m) cl
+    pout = detectOut (out m) cl
     detect_ re = detect (re m) cl
     pdep = detect_ dep
     psys = detect_ sys
@@ -85,17 +80,10 @@ sys comment =
   Regex.string (comment ++ " : sys ")
     *> Regex.many (Regex.psym (not <. Char.isSpace))
 
-out :: [Char] -> Regex.RE Char Out
+out :: [Char] -> Regex.RE Char String
 out comment =
   Regex.string (comment ++ " : out ")
     *> Regex.many (Regex.psym (/= ' '))
-    /> Bin
-
-lib :: [Char] -> Regex.RE Char Out
-lib comment =
-  Regex.string (comment ++ " : lib ")
-    *> Regex.many (Regex.psym (/= ' '))
-    /> Lib
 
 arg :: [Char] -> Regex.RE Char Arg
 arg comment =