rubyx/lib/vool/class_expression.rb
Torsten Rüger 3df54910cc rename singleton_class to single_class and misc
was clashing with real ruby method name
also many superclass mismatch fixes
some misc
2019-09-24 17:25:19 +03:00

101 lines
3.4 KiB
Ruby

module Vool
# This represents a class at the vool level. Vool is a syntax tree,
# so here the only child (or children) is a body.
# Body may either be a MethodStatement, or Statements (either empty or
# containing MethodStatement)
#
# We store the class name and the parfait class
#
# The Parfait class gets created by to_parfait, ie only after that is the clazz
# attribute set.
#
class ClassExpression < Expression
attr_reader :name, :super_class_name , :body
attr_reader :clazz
def initialize( name , supe , body)
@name = name
@super_class_name = supe || :Object
case body
when MethodExpression
@body = Statements.new([body])
when Statements
@body = body
when nil
@body = Statements.new([])
else
raise "what body #{body}"
end
end
# This creates the Parfait class.
# Creating the class involves creating the instance_type (or an initial version)
# which means knowing all used names. So we go through the code looking for
# InstanceVariables or InstanceVariable Assignments, to do that.
def to_parfait
@clazz = Parfait.object_space.get_class_by_name(@name )
if(@clazz)
if( @super_class_name != clazz.super_class_name)
raise "Superclass mismatch for #{@name} , was #{clazz.super_class_name}, now: #{super_class_name}"
end
else
@clazz = Parfait.object_space.create_class(@name , @super_class_name )
end
create_types
@body.statements.each {|meth| meth.to_parfait(@clazz)}
@clazz
end
# We transforms every method (class and object)
# Other statements are not yet allowed (baring in mind that attribute
# accessors are transformed to methods in the ruby layer )
#
# As there is no class equivalnet in code, a MomCollection is returned,
# which is just a list of Mom::MethodCompilers
# The compilers help to transform the code further, into Risc next
def to_mom( _ )
method_compilers = body.statements.collect do |node|
case node
when MethodExpression
node.to_mom(@clazz)
when ClassMethodExpression
node.to_mom(@clazz.single_class)
else
raise "Only methods for now #{node.class}:#{node}"
end
end
Mom::MomCollection.new(method_compilers)
end
# goes through the code looking for instance variables and their assignments.
# Adding each to the respective type, ie class or singleton_class, depending
# on if they are instance or class instance variables.
#
# Class variables are deemed a design mistake, ie not implemented (yet)
def create_types
self.body.statements.each do |node|
case node
when MethodExpression
target = @clazz
when ClassMethodExpression
target = @clazz.single_class
else
raise "Only methods for now #{node.class}:#{node}"
end
node.each do |exp|
case exp
when InstanceVariable, IvarAssignment
target.add_instance_variable( exp.name , :Object )
when ClassVariable #, ClassVarAssignment
raise "Class variables not implemented #{node.name}"
end
end
end
end
def to_s(depth = 0)
derive = super_class_name ? "< #{super_class_name}" : ""
at_depth(depth , "class #{name} #{derive}\n#{@body.to_s(depth + 1)}\nend")
end
end
end