def expr(state, node):
"""typecheck expression nodes"""
with state.current(node), tool.debug_scope(node) as scope:
t = type(node)
rule = dispatch.get(t, None)
if rule:
res = state.pure(rule(state, node))
scope[0] += " : " + res.show()
return res
# and now for the experimental stuff
if t is ast.Sel:
# attribute selection literals
# attribute type
attr_type = state.fresh()
# row polymorphism happens here
# FIXME broken encapsulation
rest_type = row.Var(state.depth)
return state.pure(row.Extension(node.attr, attr_type, rest_type) >> attr_type)
elif t is ast.GenCheck:
arg_type = expr(state, node.expr)
# TODO is this even right ?
if type(arg_type) is not Var:
raise error.Type("gencheck argument type must be a type variable")
# try to generalize
poly = state.generalize(arg_type)
# generalization failed
if not poly.bound:
raise GenCheckError()
return state.pure(arg_type)
elif t is ast.Move:
arg_type = expr(state, node.expr)
# TODO typeclass constraint ?
# erase from scope
del state[node.expr.name]
return state.pure(arg_type)
else:
raise error.Type("unimplemented lol: {0}".format(node))
poly = hm.toplevel(ts, node )
try:
out = node.name
except AttributeError:
out = '-'
out += ' : ' + str(poly)
ts.cleanup()
if not args.codegen:
print(out)
continue
with tool.debug_scope('closure conversion'):
# closure conversion
node = closure.toplevel( closure.State(), node)
# typecheck closure conversion
with tool.debug_scope('typecheck closure conversion'):
poly = hm.toplevel(cc, node )
tool.debug('closure conversion type:', poly)
with tool.debug_scope("codegen"):
code = codegen.toplevel(cs, node)
if code and type(node) in ast.expression_types:
code = codegen.print_expr(cs, poly.body, code, out)
