1 files changed, 36 insertions, 0 deletions
diff --git a/Biz/Repl.py b/Biz/Repl.py
new file mode 100644
index 0000000..0732fae
--- /dev/null
+++ b/Biz/Repl.py
@@ -0,0 +1,36 @@
+"""
+This module attempts to emulate the workflow of ghci or lisp repls. It uses
+importlib to load a namespace from the given path. It then binds 'r()' to a
+function that reloads the same namespace.
+"""
+
+import importlib
+import sys
+
+
+def use(ns: str, path: str) -> None:
+    """
+    Load or reload the module named 'ns' from 'path'.  Like `use` in the Guile
+    Scheme repl.
+    """
+    spec = importlib.util.spec_from_file_location(ns, path)
+    module = importlib.util.module_from_spec(spec)
+    # delete module and its imported names if its already loaded
+    if ns in sys.modules:
+        del sys.modules[ns]
+        for name in module.__dict__:
+            if name in globals():
+                del globals()[name]
+    sys.modules[ns] = module
+    spec.loader.exec_module(module)
+    names = [x for x in module.__dict__]
+    globals().update({k: getattr(module, k) for k in names})
+
+
+if __name__ == "__main__":
+    NS = sys.argv[1]
+    PATH = sys.argv[2]
+    use(NS, PATH)
+
+    def r():
+        return use(NS, PATH)