rpl.rb/lib/core/branch.rb
2021-12-09 16:32:03 +01:00

55 lines
1.7 KiB
Ruby

# frozen_string_literal: true
module Rpl
module Lang
module Core
module_function
# ( x prg -- … ) run PRG X times putting i(counter) on the stack before each run
def times( stack, dictionary )
stack, args = Rpl::Lang::Core.stack_extract( stack, [:any, %i[numeric]] )
args[1][:value].times do |i|
counter = { value: i, type: :numeric, base: 10 }
stack << counter << args[0]
stack, dictionary = Rpl::Lang::Core.eval( stack, dictionary )
end
[stack, dictionary]
end
# ( x y prg -- … ) run PRG (Y - X) times putting i(counter) on the stack before each run
def loop( stack, dictionary )
stack, args = Rpl::Lang::Core.stack_extract( stack, [:any, %i[numeric], %i[numeric]] )
(args[2][:value]..args[1][:value]).each do |i|
counter = { value: i, type: :numeric, base: 10 }
stack << counter << args[0]
stack, dictionary = Rpl::Lang::Core.eval( stack, dictionary )
end
[stack, dictionary]
end
# similar to if-then-else-end, <test-instruction> <true-instruction> <false-instruction> ifte
def ifte( stack, dictionary )
stack, args = Rpl::Lang::Core.stack_extract( stack, [:any, :any, %i[boolean]] )
stack << args[ args[2][:value] ? 1 : 0 ]
Rpl::Lang::Core.eval( stack, dictionary )
end
# Implemented in Rpl
# similar to if-then-end, <test-instruction> <true-instruction> ift
def ift( stack, dictionary )
stack << { value: '« « nop » ifte »',
type: :program }
Rpl::Lang::Core.eval( stack, dictionary )
end
end
end
end