daviddoji/example-code-2e
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

sync from Atlas

Browse Source
This commit is contained in:
Luciano Ramalho 2021-09-20 10:39:31 -03:00
commit c93076ac2b
1 changed files with 8 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
18-with-match/lispy/py3.10/lis.py
View File

@ -140,7 +140,10 @@ def lispstr(exp: object) -> str:
################ Evaluator
# tag::EVALUATE[]
KEYWORDS = ['quote', 'if', 'lambda', 'define', 'set!']
KEYWORDS = {'quote', 'if', 'lambda', 'define', 'set!'}
def is_keyword(s: Any) -> bool:
return isinstance(s, Symbol) and s in KEYWORDS
def evaluate(exp: Expression, env: Environment) -> Any:
"Evaluate an expression in an environment."
@ -164,7 +167,11 @@ def evaluate(exp: Expression, env: Environment) -> Any:
env[name] = Procedure(parms, body, env)
case ['set!', Symbol(var), value_exp]:
env.change(var, evaluate(value_exp, env))
<<<<<<< HEAD
case [func_exp, *args] if func_exp not in KEYWORDS:
=======
case [func_exp, *args] if not is_keyword(func_exp):
>>>>>>> 3ecfb212c6273122797c76876d6b373b2cb94fa6
proc = evaluate(func_exp, env)
values = [evaluate(arg, env) for arg in args]
return proc(*values)