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mal/impls/rpython/env.py
Joel Martin 8a19f60386 Move implementations into impls/ dir
- Reorder README to have implementation list after "learning tool"
  bullet.

- This also moves tests/ and libs/ into impls. It would be preferrable
  to have these directories at the top level.  However, this causes
  difficulties with the wasm implementations which need pre-open
  directories and have trouble with paths starting with "../../". So
  in lieu of that, symlink those directories to the top-level.

- Move the run_argv_test.sh script into the tests directory for
  general hygiene.
2020-02-10 23:50:16 -06:00

41 lines
1.4 KiB
Python

from mal_types import MalType, MalSym, MalList, throw_str
# Environment
class Env():
def __init__(self, outer=None, binds=None, exprs=None):
self.data = {}
self.outer = outer or None
if binds:
assert isinstance(binds, MalList) and isinstance(exprs, MalList)
for i in range(len(binds)):
bind = binds[i]
if not isinstance(bind, MalSym):
throw_str("env bind value is not a symbol")
if bind.value == u"&":
bind = binds[i+1]
if not isinstance(bind, MalSym):
throw_str("env bind value is not a symbol")
self.data[bind.value] = exprs.slice(i)
break
else:
self.data[bind.value] = exprs[i]
def find(self, key):
assert isinstance(key, MalSym)
if key.value in self.data: return self
elif self.outer: return self.outer.find(key)
else: return None
def set(self, key, value):
assert isinstance(key, MalSym)
assert isinstance(value, MalType)
self.data[key.value] = value
return value
def get(self, key):
assert isinstance(key, MalSym)
env = self.find(key)
if not env: throw_str("'" + str(key.value) + "' not found")
return env.data[key.value]