rubyx/lib/bosl/compiler/if_expression.rb
Torsten Ruger f4a4ccb98e several larger changes came together, bit of cleaning too
- all code must be in functions (which must be in classes).
— changes a fair few tests
— also changes api, as method is not recursive, not passed around
- all state in instance vars in compiler (no accessors)
- class is another such variable, surely more coming
all green again
2015-10-06 00:27:13 +03:00

39 lines
1.5 KiB
Ruby

module Bosl
Compiler.class_eval do
# if - attr_reader :cond, :if_true, :if_false
def on_if expression
condition , if_true , if_false = *expression
condition = condition.first
# to execute the logic as the if states it, the blocks are the other way around
# so we can the jump over the else if true ,
# and the else joins unconditionally after the true_block
merge_block = @method.source.new_block "if_merge" # last one, created first
true_block = @method.source.new_block "if_true" # second, linked in after current, before merge
false_block = @method.source.new_block "if_false" # directly next in order, ie if we don't jump we land here
is = process(condition )
# TODO should/will use different branches for different conditions.
# just a scetch : cond_val = cond_val.is_true?(method) unless cond_val.is_a? BranchCondition
@method.source.add_code Virtual::IsTrueBranch.new( true_block )
# compile the true block (as we think of it first, even it is second in sequential order)
@method.source.current true_block
last = process_all(if_true).last
# compile the false block
@method.source.current false_block
last = process_all(if_false).last if if_false
@method.source.add_code Virtual::UnconditionalBranch.new( merge_block )
#puts "compiled if: end"
@method.source.current merge_block
#TODO should return the union of the true and false types
last
end
end
end