eval can only see locals

[gilch]

Eval works on symbols for modules:

=> (import operator)
import operator
=> (eval 'operator)
from hy.importer import hy_eval
from hy import HySymbol
hy_eval(HySymbol('operator'), locals(), '__console__')
<module 'operator' from 'C:\\Python34\\Scripts\\env-hy\\lib\\operator.py'>

Functions can return modules:

=> ((fn [] operator))
def _hy_anon_fn_1():
    return operator
_hy_anon_fn_1()
<module 'operator' from 'C:\\Python34\\Scripts\\env-hy\\lib\\operator.py'>

Functions can return the result of an eval:

=> ((fn [] (eval 'first)))
from hy.importer import hy_eval
from hy import HySymbol

def _hy_anon_fn_1():
    return hy_eval(HySymbol('first'), locals(), '__console__')
_hy_anon_fn_1()
<function first at 0x000000000369DC80>

But not if it's a module!

=> ((fn [] (eval 'operator)))
from hy.importer import hy_eval
from hy import HySymbol

def _hy_anon_fn_1():
    return hy_eval(HySymbol('operator'), locals(), '__console__')
_hy_anon_fn_1()
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "<input>", line 1, in _hy_anon_fn_1
  File "c:\users\me\code\repos\hy\hy\importer.py", line 134, in hy_eval
    return eval(ast_compile(expr, "<eval>", "eval"), namespace)
  File "<eval>", line 1, in <module>
NameError: name 'operator' is not defined

I am surprised by this. Are you?

[gilch]

It's not just modules. I found a simpler illustration:

=> (def spam 42)
spam = 42
=> (eval 'spam)
from hy.importer import hy_eval
from hy import HySymbol
hy_eval(HySymbol('spam'), locals(), '__console__')
42
=> ((fn [] (eval 'spam)))
from hy.importer import hy_eval
from hy import HySymbol

def _hy_anon_fn_1():
    return hy_eval(HySymbol('spam'), locals(), '__console__')
_hy_anon_fn_1()
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "<input>", line 1, in _hy_anon_fn_1
  File "c:\users\me\code\repos\hy\hy\importer.py", line 134, in hy_eval
    return eval(ast_compile(expr, "<eval>", "eval"), namespace)
  File "<eval>", line 1, in <module>
NameError: name 'spam' is not defined
=> ((fn [] (eval 'spam (globals))))
from hy.importer import hy_eval
from hy import HySymbol

def _hy_anon_fn_1():
    return hy_eval(HySymbol('spam'), globals(), '__console__')
_hy_anon_fn_1()
42

The equivalent Clojure works:

user=> (def spam 42)
#'user/spam
user=> (eval 'spam)
42
user=> ((fn [] (eval 'spam)))
42
user=>

Common Lisp too:

* (defvar spam 42)

SPAM
* ((lambda () (eval 'spam)))

42
*

Even Racket Scheme (if anyone cares about Racket):

> (define spam 42)
> ((lambda () (eval 'spam)))
42
> 

[refi64]

Have a fix in the works; just writing the tests.

[allison-casey]

I don't know how yet, but this looks to be fixed.

[Kodiologist]

Don't feel like you have to find the change that fixed it. The important thing is just ensuring it's fixed.