def eval(cls, forms, var_env, func_env, macro_env):
if isinstance(forms, Null):
# Returns nil.
return forms
elif isinstance(forms, Symbol):
# Gets symbol_name, package_name, and status_check.
symbol_name, package_name, status_check = PackageManager.split_symbol_name(
forms.value)
# Gets the value binded by the symbol.
# When package_name is None, the package becomes PackageManager.current_package.
try:
# Tries to get the value from lexical environment in current package.
return var_env.find(symbol_name)[symbol_name]
except LookupError:
# Tries to get the value from another package.
return PackageManager.find(symbol_name,
package_name,
status_check,
env='VARIABLE')[symbol_name]
finally:
# If package_name is 'KEYWORD', sets keyword represented by symbol_name.
if package_name == 'KEYWORD':
assign_helper(symbol_name, Keyword(symbol_name),
package_name, 'VARIABLE', ':EXTERNAL')
return PackageManager.find(symbol_name,
package_name,
status_check,
env='VARIABLE')[symbol_name]
elif not isinstance(forms, Cons):
# If an atom is given, returns itself.
return forms
else:
# Binds function object.
if isinstance(forms.car, Cons):
# If lambda expression is given, it is bound as an anonymous function.
# Other than that, it is bound from predefined functions involving special
func = cls.eval(forms.car, var_env, func_env, macro_env)
else:
# Gets symbol_name, package_name, and status_check.
func_name, package_name, status_check = PackageManager.split_symbol_name(
forms.car.value)
# Gets the function binded by the symbol.
# When package_name is None, the package becomes PackageManager.current_package.
try:
# Tries to get the function from lexical environment in current package.
func = func_env.find(func_name)[func_name]
except LookupError:
# Tries to get the function from another package.
func = PackageManager.find(func_name,
package_name,
status_check,
env='FUNCTION')[func_name]
return func(forms.cdr, var_env, func_env, macro_env)
def testPackageManager_find(self):
# PackageManger.find results an environment that have value assigned by symbol.
# The package that have the environment is shown by package_name.
# symbol_name, package_name, status_check is given by PackageManger.split_symbol.
# Checks an environment using *PACKAGE* in current package.
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP::*PACKAGE*')
env = PackageManager.find(symbol_name, package_name, status_check)
self.assertIsInstance(env, Environment)
self.assertTrue('*PACKAGE*' in env)
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP:*PACKAGE*')
env = PackageManager.find(symbol_name, package_name, status_check)
self.assertIsInstance(env, Environment)
self.assertTrue('*PACKAGE*' in env)
symbol_name, package_name, status_check = PackageManager.split_symbol_name('*PACKAGE*')
env = PackageManager.find(symbol_name, package_name, status_check)
self.assertIsInstance(env, Environment)
self.assertTrue('*PACKAGE*' in env)
# Checks an environment using *PACKAGE* in another package.
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP-USER::*PACKAGE*')
env = PackageManager.find(symbol_name, package_name, status_check)
self.assertIsInstance(env, Environment)
self.assertTrue('*PACKAGE*' in env)
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP-USER:*PACKAGE*')
env = PackageManager.find(symbol_name, package_name, status_check)
self.assertIsInstance(env, Environment)
self.assertTrue('*PACKAGE*' in env)
def expand(cls, forms, var_env, func_env, macro_env):
if not isinstance(forms, Cons):
# If an atom is given, returns itself.
return forms
elif isinstance(forms.car,
Symbol): # and forms.car.value in macro_env:
# Gets symbol_name, package_name, and status_check.
macro_name, package_name, status_check = PackageManager.split_symbol_name(
forms.car.value)
# Gets the macro binded by the symbol.
# When package_name is None, the package becomes PackageManager.current_package.
try:
# Tries to get the function from lexical environment in current package.
macro = macro_env.find(macro_name)[macro_name]
except LookupError:
try:
macro = PackageManager.find(macro_name,
package_name,
status_check,
env='MACRO')[macro_name]
except LookupError:
return Cons(
forms.car,
cls.recusive_expand(forms.cdr, var_env, func_env,
macro_env))
return macro(forms.cdr, var_env, func_env, macro_env)
else:
return Cons(cls.expand(forms.car, var_env, func_env, macro_env),
cls.expand(forms.cdr, var_env, func_env, macro_env))
def __call__(self, forms, var_env, func_env, macro_env):
"""Behavior of FunctionSpecialOperator.
"""
if isinstance(forms.car, Cons) and forms.car.car is Symbol('LAMBDA'):
return Lambda(forms.car.cdr, var_env, func_env, macro_env)
else:
# Gets symbol_name, package_name, and status_check.
func_name, package_name, status_check = PackageManager.split_symbol_name(
forms.car.value)
# Gets the function binded by the symbol.
try:
# First, tries to get the value from lexical environment.
return func_env.find(func_name)[func_name]
except LookupError:
# If LookupError is raised, tries to get from another package.
return PackageManager.find(func_name,
package_name,
status_check,
env='FUNCTION')[func_name]
def testPackageManager_split_symbol_name(self):
# PackageManager.split_symbol_name splits symbol_name including package_name
# and returns status_check indicating whether it needs status check or not.
# When symbol_name is not KEYWORD,
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP::CAR')
self.assertEqual(symbol_name, 'CAR')
self.assertEqual(package_name, 'COMMON-LISP')
self.assertFalse(status_check)
symbol_name, package_name, status_check = PackageManager.split_symbol_name('COMMON-LISP:CAR')
self.assertEqual(symbol_name, 'CAR')
self.assertEqual(package_name, 'COMMON-LISP')
self.assertTrue(status_check)
symbol_name, package_name, status_check = PackageManager.split_symbol_name('CAR')
self.assertEqual(symbol_name, 'CAR')
self.assertEqual(package_name, None)
self.assertFalse(status_check)
# When symbol_name is KEYWORD,
sybmol_name, package_name, status_check = PackageManager.split_symbol_name('KEYWORD::EXTERNAL')
self.assertEqual(sybmol_name, ':EXTERNAL')
self.assertEqual(package_name, 'KEYWORD')
self.assertFalse(status_check)
sybmol_name, package_name, status_check = PackageManager.split_symbol_name('KEYWORD:EXTERNAL')
self.assertEqual(sybmol_name, ':EXTERNAL')
self.assertEqual(package_name, 'KEYWORD')
self.assertFalse(status_check)
sybmol_name, package_name, status_check = PackageManager.split_symbol_name(':EXTERNAL')
self.assertEqual(sybmol_name, ':EXTERNAL')
self.assertEqual(package_name, 'KEYWORD')
self.assertFalse(status_check)
