Change eval from a special form to a function

NEWS

@@ -4,6 +4,7 @@ Changes from 0.13.0
    * Single-character "sharp macros" changed to "tag macros", which can have
      longer names
    * Periods are no longer allowed in keywords
+   * `eval` is now a function instead of a special form
 
    [ Bug Fixes ]
    * Numeric literals are no longer parsed as symbols when followed by a dot

docs/language/api.rst

@@ -863,27 +863,6 @@ doto
   => collection
   [2 1]
 
-eval
-----
-
-``eval`` evaluates a quoted expression and returns the value. The optional
-second and third arguments specify the dictionary of globals to use and the
-module name. The globals dictionary defaults to ``(local)`` and the module name
-defaults to the name of the current module.
-
-.. code-block:: clj
-
-   => (eval '(print "Hello World"))
-   "Hello World"
-
-If you want to evaluate a string, use ``read-str`` to convert it to a
-form first:
-
-.. code-block:: clj
-
-   => (eval (read-str "(+ 1 1)"))
-   2
-
 
 eval-and-compile
 ----------------

docs/language/core.rst

@@ -230,6 +230,30 @@ Returns ``True`` if *coll* is empty. Equivalent to ``(= 0 (len coll))``.
    False
 
 
+.. _eval-fn:
+
+eval
+----
+
+``eval`` evaluates a quoted expression and returns the value. The optional
+second and third arguments specify the dictionary of globals to use and the
+module name. The globals dictionary defaults to ``(local)`` and the module name
+defaults to the name of the current module.
+
+.. code-block:: clj
+
+   => (eval '(print "Hello World"))
+   "Hello World"
+
+If you want to evaluate a string, use ``read-str`` to convert it to a
+form first:
+
+.. code-block:: clj
+
+   => (eval (read-str "(+ 1 1)"))
+   2
+
+
 .. _every?-fn:
 
 every?

hy/compiler.py

@@ -706,31 +706,6 @@ class HyASTCompiler(object):
         raise HyTypeError(expr,
                           "`%s' can't be used at the top-level" % expr[0])
 
-    @builds("eval")
-    @checkargs(min=1, max=3)
-    def compile_eval(self, expr):
-        expr.pop(0)
-
-        if not isinstance(expr[0], (HyExpression, HySymbol)):
-            raise HyTypeError(expr, "expression expected as first argument")
-
-        elist = [HySymbol("hy_eval")] + [expr[0]]
-        if len(expr) >= 2:
-            elist.append(expr[1])
-        else:
-            elist.append(HyExpression([HySymbol("locals")]))
-
-        if len(expr) == 3:
-            elist.append(expr[2])
-        else:
-            elist.append(HyString(self.module_name))
-
-        ret = self.compile(HyExpression(elist).replace(expr))
-
-        ret.add_imports("hy.importer", ["hy_eval"])
-
-        return ret
-
     @builds("do")
     def compile_do(self, expression):
         expression.pop(0)

hy/core/language.hy

@@ -19,6 +19,7 @@
 (import [hy.models [HyCons HySymbol HyKeyword]])
 (import [hy.lex [LexException PrematureEndOfInput tokenize]])
 (import [hy.compiler [HyASTCompiler]])
+(import [hy.importer [hy-eval :as eval]])
 
 (defn butlast [coll]
   "Returns coll except of last element."
@@ -469,7 +470,7 @@
 (def *exports*
   '[*map accumulate butlast calling-module-name chain coll? combinations
     comp complement compress cons cons? constantly count cycle dec distinct
-    disassemble drop drop-last drop-while empty? even? every? first filter
+    disassemble drop drop-last drop-while empty? eval even? every? first filter
     flatten float? fraction gensym group-by identity inc input instance?
     integer integer? integer-char? interleave interpose islice iterable?
     iterate iterator? juxt keyword keyword? last list* macroexpand

hy/importer.py

@@ -14,6 +14,7 @@ import struct
 import imp
 import sys
 import ast
+import inspect
 import os
 import __future__
 
@@ -142,7 +143,14 @@ def import_buffer_to_module(module_name, buf):
     return mod
 
 
-def hy_eval(hytree, namespace, module_name, ast_callback=None):
+def hy_eval(hytree, namespace=None, module_name=None, ast_callback=None):
+    if namespace is None:
+        frame = inspect.stack()[1][0]
+        namespace = inspect.getargvalues(frame).locals
+    if module_name is None:
+        m = inspect.getmodule(inspect.stack()[1][0])
+        module_name = '__eval__' if m is None else m.__name__
+
     foo = HyObject()
     foo.start_line = 0
     foo.end_line = 0

tests/native_tests/language.hy

@@ -1087,10 +1087,11 @@
 (defn test-eval-failure []
   "NATIVE: test eval failure modes"
   ; yo dawg
-  (try (eval '(eval)) (except [e HyTypeError]) (else (assert False)))
+  (import [hy.compiler [HyCompileError]])
-  (try (eval '(eval "snafu")) (except [e HyTypeError]) (else (assert False)))
+  (try (eval '(eval)) (except [e TypeError]) (else (assert False)))
+  (try (eval '(eval "snafu")) (except [e HyCompileError]) (else (assert False)))
   (try (eval 'False []) (except [e HyTypeError]) (else (assert False)))
-  (try (eval 'False {} 1) (except [e HyTypeError]) (else (assert False))))
+  (try (eval 'False {} 1) (except [e TypeError]) (else (assert False))))
 
 
 (defn test-import-syntax []