py, compiler: Add basic support for A=const(123).

You can now do:

    X = const(123)
    Y = const(456 + X)

and the compiler will replace X and Y with their values.

See discussion in issue #266 and issue #573.

1 files changed, 11 insertions, 0 deletions

diff --git a/tests/micropython/const.py b/tests/micropython/const.py
new file mode 100644
index 000000000..457365c50
--- /dev/null
+++ b/tests/micropython/const.py
@@ -0,0 +1,11 @@
+# test constant optimisation
+
+X = const(123)
+Y = const(X + 456)
+
+print(X, Y + 1)
+
+def f():
+    print(X, Y + 1)
+
+f()