def _make_module_parser(*, global_variable, function, class_, module_name):
global_stmt = Any(
global_variable.map(lambda x: ('var', x)),
function.map(lambda x: ('func', x)),
class_.map(lambda x: ('cls', x)),
)
module_pattern = All(
import_stmt.map(lambda x: ('import', x)).repeat(),
global_stmt.repeat(),
).flatten()
def module_callback(m):
imports = []
vars = []
funcs = []
clss = []
for kind, node in m.value:
if kind == 'import':
imports.append(node)
elif kind == 'var':
vars.append(node)
elif kind == 'func':
funcs.append(node)
elif kind == 'cls':
clss.append(node)
else:
raise base.Error([node.mark], f'FUBAR: {kind}: {node}')
return ast.Module(
mark=m.mark,
name=module_name,
imports=tuple(imports),
vars=tuple(vars),
funcs=tuple(funcs),
clss=tuple(clss),
)
return module_pattern.fatmap(module_callback)
def _make_combined_parser(*, module_name, importable_id, exportable_id, type_,
expression, block, global_dict, module_scope):
# We can perform some basic validations if the global_dict
# is available to us.
validate = global_dict is not None
global_variable = All(
type_,
exportable_id,
'=',
expression.required(),
Any(';').required(),
).fatmap(lambda m: ast.GlobalVariable(
mark=m.mark,
type=m.value[0],
name=m.value[1],
expr=m.value[3] if global_dict is None else m.value[3](global_dict),
))
parameter = All(type_, 'ID').fatmap(lambda m: ast.Parameter(
mark=m.mark,
type=m.value[0],
name=m.value[1],
))
parameters = All(
'(',
parameter.join(',').map(tuple),
')',
).map(lambda args: tuple(args[1]))
############
# Function
############
function_pattern = All(
native, # 0: native
type_, # 1: return type
exportable_id, # 2: name
parameters, # 3: parameters
Any(
block,
Any(';').map(lambda x: None),
), # 4: body
)
def function_callback(m):
native = m.value[0]
rtype = m.value[1]
name = m.value[2]
params = m.value[3]
body_thunk = m.value[4]
if body_thunk is None:
body = None
else:
scope = Scope(module_scope)
for param in params:
scope[param.name] = param
body = body_thunk(scope)
if validate:
if native and body:
raise base.Error([m.mark],
'Native functions cannot have a body')
if not native and not body:
raise base.Error([m.mark],
'Non-native functions must have a body')
return ast.Function(
mark=m.mark,
rtype=rtype,
name=name,
params=params,
body=body,
)
function = function_pattern.fatmap(function_callback)
############
# Field
############
field_thunk = (All(type_, 'ID',
';').fatmap(lambda m: lambda scope: ast.Field(
mark=m.mark,
type=m.value[0],
name=f'{scope["@class_name"]}.{m.value[1]}',
)))
#################
# Method (thunk)
#################
method_pattern = All(
type_, # 0: return type
'ID', # 1: name
parameters, # 2: parameters
Any(
block,
Any(';').map(lambda x: None),
), # 3: body
)
def method_callback(m):
def inner_callback(outer_scope):
scope = Scope(outer_scope)
rtype = m.value[0]
name = f'{scope["@class_name"]}#{m.value[1]}'
params = m.value[2]
body_thunk = m.value[3]
if body_thunk is None:
body = None
else:
for param in params:
scope[param.name] = param
body = body_thunk(scope)
return ast.Method(
mark=m.mark,
rtype=rtype,
name=name,
params=params,
body=body,
)
return inner_callback
method_thunk = method_pattern.fatmap(method_callback)
############
# Class
############
base_class = Any(
All(':', importable_id).map(lambda args: args[1]),
All().map(lambda args: None),
)
class_pattern = All(
native, # 0: native
'class', # 1
exportable_id, # 2: name
base_class, # 3: base/super class
'{', # 4
field_thunk.repeat(), # 5: fields
method_thunk.repeat(), # 6: methods
'}', # 7
)
def class_callback(m):
native = m.value[0]
class_name = m.value[2]
declared_base = m.value[3]
field_thunks = m.value[5]
method_thunks = m.value[6]
base = (ast.OBJECT if declared_base is None
and class_name != ast.OBJECT else declared_base)
scope = Scope(module_scope)
scope['@class_name'] = class_name
fields = tuple(ft(scope) for ft in field_thunks)
methods = tuple(mt(scope) for mt in method_thunks)
if validate:
for method in methods:
if native and method.body:
raise base.Error(
[m.mark, method.mark],
'Native classes cannot have method bodies',
)
if not native and not method.body:
raise base.Error(
[m.mark, method.mark],
'Non-native classes cannot have native methods',
)
if native and fields:
raise base.Error(
[m.mark, fields[0].mark],
'Native classes cannot have fields',
)
return ast.Class(
mark=m.mark,
native=native,
name=class_name,
base=base,
fields=fields,
methods=methods,
)
class_ = class_pattern.fatmap(class_callback)
module = _make_module_parser(
global_variable=global_variable,
function=function,
class_=class_,
module_name=module_name,
)
return module
