def __init__(self, scope=None):
"""Initialize the Interpreter instance.
If scope is present, it will be passed to the push method of the instance's ScopeStack.
"""
self.scope = ScopeStack(global_scope)
if scope:
self.scope.push(scope)
self.resolver = Resolver(self.scope)
class Interpreter(object):
"""The Interpreter class executes compiled pxp code."""
def __init__(self, scope=None):
"""Initialize the Interpreter instance.
If scope is present, it will be passed to the push method of the instance's ScopeStack.
"""
self.scope = ScopeStack(global_scope)
if scope:
self.scope.push(scope)
self.resolver = Resolver(self.scope)
def interpret(self, source):
"""Compile and execute source code.
source is pxp source text.
"""
# Give the compiler all the non-global_scope scopes.
compiler = Compiler(source, self.scope.scopes[1:])
program = compiler.compile()
return self.execute(program)
@staticmethod
def get_type(program):
"""Returns the return type of the return statement of the compiled program."""
_, ptype, *_ = program
return ptype
def execute(self, program):
"""Execute compiled pxp instructions."""
with self.scope.using(DictScope()):
_, ptype, assignments, (_, return_exp) = program
for assignment in assignments:
self._assign(assignment)
return self.resolver.resolve(return_exp)
def _assign(self, assignment):
"""Handle an assignment instruction."""
_, name, value = assignment
self.scope.set_variable(name, value)