Making headway towards a runnable state

projects/lilith/BUILD

@@ -1,5 +1,6 @@
 py_project(
-    name = "lib",
+    name = "lilith",
+    main = "src/python/lilith/__main__.py",
     lib_deps = [
         py_requirement("lark"),
         py_requirement("pyyaml"),
@@ -9,16 +10,3 @@ py_project(
         py_requirement("hypothesis"),
     ],
 )
-
-zapp_binary(
-    name = "lilith",
-    main = "src/python/lilith/__main__.py",
-    deps = [
-        ":lib",
-        # FIXME: Due to zapp bug(s), replicating requirements here.
-        py_requirement("lark"),
-        py_requirement("pyyaml"),
-        py_requirement("markdown"),
-        py_requirement("prompt_toolkit"),
-    ],
-)

projects/lilith/src/lilith/designdoc.lil

@@ -36,7 +36,7 @@ FIXME: We need the object language
 
 !def[openapi, yaml[]]
 
-!def[main, lilith[]]
+!def[main, lang[lilith]]
 ; is importing a bang-operation?
 
 print[str.join["", [pitch, syntax]]]

projects/lilith/src/python/lilith/__main__.py

@@ -75,21 +75,23 @@ def batch(opts, args, runtime):
     main = Symbol(main)
 
     # Register
-    runtime.modules[mod.name] = mod
+    runtime.modules.update({mod.name: mod})
 
     print("DEBUG: batch mode")
     print(
         yaml.dump(
             {
                 "type": "runtime",
-                "name": runtime.name,
+                "name": runtime.name.name,
                 "modules": {
-                    m.name: {
+                    m.name.name: {
                         "defs": {dname.name: repr(d) for dname, d in m.defs.items()}
                     }
                     for m in runtime.modules.values()
                 },
-            }
+            },
+            default_flow_style=False,
+            sort_keys=False,
         )
     )
 
@@ -125,11 +127,27 @@ if __name__ == "__main__":
             sys.path.insert(0, _e)
 
     # Building up a bootstrap interface for going out to many Python features.
-    runtime = Runtime("__runtime__", Symbol(opts.prelude), {})
+    runtime = Runtime(Symbol("__runtime__"), Symbol(opts.prelude), {})
+
+    def _lil(runtime=None,
+             module=None,
+             body=None,
+             name=None):
+        """The implementation of the Lilith lang as an eval type."""
+        expr = parse_expr(body)
+        return eval(runtime, module, Bindings(), expr)
+
     bootstrap = Module(
-        "lilith.bootstrap",
+        Symbol("lilith.bootstrap"),
         [],
-        {Symbol("py"): lambda *args, body=None, **kwargs: eval(body)},
+        {
+            # The foundational meaning of lang[]
+            Symbol("lang"): lambda evaluator, body=None: evaluator(body),
+            # The Python FFI escape hatch
+            Symbol("py"): lambda *args, body=None, **kwargs: eval(body),
+            # The Lilith self-interpreter
+            Symbol("lilith"): _lil,
+         },
     )
     runtime.modules[Symbol(bootstrap.name)] = bootstrap
     prelude_mod = read_buffer(

projects/lilith/src/python/lilith/grammar.lark

@@ -10,10 +10,9 @@ STRING: /""".*?"""/ | /".*?"/
 int: INT
 float: FLOAT
 number: int | float
-word: "nil" -> nil
-    | "true" -> true
-    | "false" -> false
-    | WORD ("." WORD)* -> word
+
+word: WORD ("." WORD)* -> word
+
 string: STRING
 
 list: "[" (expr ("," expr)*)? "]"
@@ -21,7 +20,14 @@ list: "[" (expr ("," expr)*)? "]"
 pair: expr ":" expr
 dict: "{" (pair ("," pair)*)? "}"
 
-atom: number | word | string | list | dict
+atom: number
+    | word
+    | string
+    | list
+    | dict
+    | "nil" -> nil
+    | "true" -> true
+    | "false" -> false
 
 application: word "[" arguments? "]"
 

projects/lilith/src/python/lilith/interpreter.py

@@ -72,9 +72,7 @@ def eval(ctx: Runtime, mod: Module, locals: Bindings, expr):
         return lookup(ctx, mod, locals, expr)
 
     elif isinstance(expr, Apply):
-        # FIXME (arrdem 2021-08-21):
-        #   Apply should be (apply <expr> <args> <kwargs>).
-        #   Now no distinction is made between strings ("") and symbols/barewords
+        # Evaluate the call target
         fun = eval(ctx, mod, locals, expr.target)
         # Evaluate the parameters
         args = eval(ctx, mod, locals, expr.args.positionals)

tools/python/defs.bzl

@@ -8,6 +8,10 @@ load("@rules_python//python:defs.bzl",
      _py_library = "py_library",
 )
 
+load("@rules_zapp//zapp:zapp.bzl",
+     "zapp_binary",
+)
+
 
 def py_requirement(*args, **kwargs):
     """A re-export of requirement()"""
@@ -146,6 +150,7 @@ py_resources = rule(
 )
 
 def py_project(name=None,
+               main=None,
                lib_srcs=None,
                lib_deps=None,
                lib_data=None,
@@ -184,8 +189,41 @@ def py_project(name=None,
                                              "**/*.pyc",
                                          ])
 
+    lib_name = name if not main else "lib"
+
     py_library(
+        name=lib_name,
+        srcs=lib_srcs,
+        deps=lib_deps,
+        data=lib_data,
+        imports=[
+            "src/python",
+            "src/resources",
+        ],
+        visibility = [
+            "//visibility:public",
+        ],
+    )
+
+    if main:
+        py_binary(
             name=name,
+            main=main,
+            srcs=lib_srcs,
+            deps=lib_deps,
+            data=lib_data,
+            imports=[
+                "src/python",
+                "src/resources",
+            ],
+            visibility = [
+                "//visibility:public",
+            ],
+        )
+
+        zapp_binary(
+            name=name + ".zapp",
+            main=main,
             srcs=lib_srcs,
             deps=lib_deps,
             data=lib_data,
@@ -203,7 +241,7 @@ def py_project(name=None,
             py_pytest(
                 name=src.split("/")[-1],
                 srcs=[src] + [f for f in test_srcs if "test_" not in f],
-                deps=[name] + (test_deps or []),
+                deps=[lib_name] + (test_deps or []),
                 data=test_data,
                 imports=[
                     "test/python",