class Pen(Struct('points count box start end')):
# XXX maybe make this (except for `points`) all an optional field in Conn
def build(self, env):
# XXX Should we require len(points) to be 2?
# Or work over each pair of successive points?
# It looks like real IDEAL requires at least 2 but ignores any left over.
assert len(
self.points) == 2, "'conn using' must connect exactly two points"
zero, one = self.points
# XXX The true semantics is problematic for us in requiring
# count to be evaluated to a number before we can instantiate
# the boxes -- so far we've never interleaved creating
# objects with solving constraints. I think we could do this
# without a massive overhaul, but I'm not gonna try
# tonight. Instead, require `count` to be a literal.
assert isinstance(self.count,
Literal), "XXX crude implementation restriction"
assert self.count.value.imag == 0
n = self.count.value.real
assert n == int(n)
n = int(n)
ps = [
Relatively(Div(Literal(i), self.count), zero, one)
for i in range(n + 1)
]
for a_exp, b_exp in zip(ps[:-1], ps[1:]):
segment = Put(
None,
self.box.prepend((Equate(
(self.start, a_exp)), Equate((self.end, b_exp)))))
segment.build(env)
class Constraints(Struct('equations')):
def build(self, env):
for lhs, rhs in self.equations:
LC.equate(lhs.evaluate(env), rhs.evaluate(env))
def draw(self, env):
pass
class Text(Struct('justified string where')):
def build(self, env):
env.add_drawer(self)
def draw(self, env):
at = self.where.evaluate(env).get_value()
renderer.text(self.string, self.justified, to_coords(at))
class Path(Struct('points')):
def build(self, env):
env.add_drawer(self)
def draw(self, env):
points = [p.evaluate(env).get_value() for p in self.points]
self.render(map(to_coords, points))
class Box(Struct('name stmts')):
def make(self, env):
for stmt in self.stmts:
stmt.build(env)
def prepend(self, stmts):
return Box(self.name, stmts + self.stmts)
class Tuple(Struct('exprs')):
def evaluate(self, env):
type_ = tuple_types[len(self.exprs)]
inst = type_.instantiate(env)
for v, expr in zip(type_.fields, self.exprs):
LC.equate(inst.mapping[v], expr.evaluate(env))
return inst
class Draw(Struct('drawables')):
def build(self, env):
pass
def draw(self, env):
for drawable in self.drawables:
drawable.draw(env)
class Div(Struct('arg1 arg2', supertype=(Expr, ))):
def evaluate(self):
combo1 = self.arg1.evaluate()
combo2 = self.arg2.evaluate()
terms2 = combo2.expand()
if varies(terms2):
raise Nonlinear()
return combo1.scale(1 / constant(terms2))
class Relatively(Struct('coord zero one')):
"""Linear interpolate/extrapolate, i.e. `coord` in the coordinate
system that places 0 at `zero` and 1 at `one`."""
def evaluate(self, env):
coord = self.coord.evaluate(env)
zero = self.zero.evaluate(env)
one = self.one.evaluate(env)
return zero + (one - zero) * coord
class Ref(Struct('name')):
def evaluate(self, env):
for frame in reversed(env.frames):
try:
return frame[self.name]
except KeyError:
pass
raise KeyError("Unbound name", self.name)
class Put(Struct('opt_name box')):
def build(self, env):
name = self.opt_name or gensym(
) # (The default name's just for debugging.)
subenv = env.spawn(name)
env.types[self.box.name].make(subenv)
define(env.frames[-1], name, subenv.frames[-1])
self.box.make(subenv)
class TupleType(Struct('fields')):
def instantiate(self, env):
inst = Instance(self)
for f in self.fields:
inst.mapping[f] = NumberInstance()
return inst
def draw(self, env):
pass
class Compass(Struct('center boundary_point')):
def build(self, env):
env.add_drawer(self)
def draw(self, env):
points = [
p.evaluate(env).get_value()
for p in (self.center, self.boundary_point)
]
renderer.circle(*map(to_coords, points))
class NonlinearFn(Struct('fn arg', supertype=(Expr, ))):
def evaluate(self):
combo = self.arg.evaluate()
terms = combo.expand()
if varies(terms):
raise Nonlinear()
value = constant(terms)
assert isinstance(value, (int, float, complex)), \
'type: %s, value: %r' % (type(value), value)
return make_constant(self.fn(value))
class VarDecl(Struct('type_id decls')):
def build(self, env):
type_ = env.types[self.type_id]
for decl in self.decls:
inst = type_.instantiate(env)
env.init(decl.id, inst)
for id, rhs in decl.params:
LC.equate(inst.mapping[id], rhs.evaluate(env))
def draw(self, env):
pass
class Equate(Struct('parts')):
defaulty = False
def build(self, env):
env.add_constrainer(self)
def constrain(self, env):
def eq(lhs, rhs):
env.constraints.append(solver.Equate(self.defaulty, lhs, rhs))
return rhs
reduce(eq, (expr.evaluate(env) for expr in self.parts))
class Environment(
Struct('types constrainers constraints drawers prefix frames')):
def spawn(self, name):
return Environment(self.types, self.constrainers, self.constraints,
self.drawers, self.prefix + name + '.',
self.frames + ({}, ))
def add_constrainer(self, constrainer):
self.constrainers.append((constrainer, self))
def add_drawer(self, drawer):
self.drawers.append((drawer, self))
class Environment(Struct('types inst')):
def spawn(self, inst):
return Environment(self.types, inst)
def init(self, id, value):
assert id not in self.inst.mapping, "Multiple def: %s" % id
self.inst.mapping[id] = value
def fetch(self, id):
assert id in self.inst.mapping, \
"Not found: %r in %r" % (id, self.inst)
return self.inst.mapping[id]
class Definition(Struct('id extends decls')):
def build(self, env):
env.types[self.id] = self
def instantiate(self, env):
inst = Instance(self)
subenv = env.spawn(inst) # XXX won't see global vars; should it?
self.populate(subenv)
return inst
def populate(self, env):
supe = self.super_definition(env)
if supe:
supe.populate(env)
for decl in self.decls:
decl.build(env)
def draw(self, env):
for drawer in self.pick_drawers(env) or env.inst.get_parts():
drawer.draw(env)
def pick_drawers(self, env):
defn = self
while defn:
decls = [decl for decl in defn.decls if isinstance(decl, Draw)]
if decls: return decls
defn = defn.super_definition(env)
return []
def super_definition(self, env):
if self.extends:
supertype = env.types[self.extends]
assert isinstance(supertype, Definition), \
"%r is not a definition" % supertype
return supertype
else:
return None
class Combine(Struct('arg1 coeff arg2', supertype=(Expr, ))):
def evaluate(self):
return self.arg1.evaluate().combine(self.coeff, self.arg2.evaluate())
class CallPrim(Struct('fn arg')):
def evaluate(self, env):
return self.fn(self.arg.evaluate(env))
class Decl(Struct('names')):
def build(self, env):
for name in self.names:
define(env.frames[-1], name,
solver.make_variable(env.prefix + name))
class Structures:
MSG_4_STRUCT = Struct('I') #4
MSG_2_STRUCT = Struct('H') #2
class VarDecl(Struct('type_id decls')):
def build(self, env):
type_ = env.types[self.type_id]
for decl in self.decls:
inst = type_.instantiate(env)
env.init(decl.id, inst)
for id, rhs in decl.params:
LC.equate(inst.mapping[id], rhs.evaluate(env))
def draw(self, env):
pass
Declarator = Struct('id params', name='Declarator')
class Constraints(Struct('equations')):
def build(self, env):
for lhs, rhs in self.equations:
LC.equate(lhs.evaluate(env), rhs.evaluate(env))
def draw(self, env):
pass
class Draw(Struct('drawables')):
def build(self, env):
pass
class Number(Struct('value')):
def evaluate(self, env):
return self.value
class Dot(Struct('base field')):
def evaluate(self, env):
return self.base.evaluate(env).mapping[self.field]
class Name(Struct('id')):
def evaluate(self, env):
return env.fetch(self.id)
class DrawFunction(Struct('fn_name')):
def draw(self, env):
draw_functions[self.fn_name](**env.inst.mapping)
class BinaryOp(Struct('arg1 arg2')):
def evaluate(self, env):
return self.operate(self.arg1.evaluate(env), self.arg2.evaluate(env))
class DrawName(Struct('name')):
def draw(self, env):
self.name.evaluate(env).draw(env)
