I am new to the Ruby scripting language.
I was learning how to generate the byte code in Ruby. I found the answer for generating the byte code.
But I don't know how to run that generated byte code. I searched the internet, but I didn't get the answer for this.
Generating a byte code:-
puts RubyVM::InstructionSequence.compile("x = 50; x > 100 ? 'foo' : 'bar'").disassemble
The output is,
== disasm: <RubyVM::InstructionSequence:<compiled>@<compiled>>==========
local table (size: 2, argc: 0 [opts: 0, rest: -1, post: 0, block: -1] s1)
[ 2] x
0000 trace 1 ( 1)
0002 putobject 50
0004 setlocal x
0006 trace 1
0008 getlocal x
0010 putobject 100
0012 opt_gt <ic:1>
0014 branchunless 20
0016 putstring "foo"
0018 leave
0019 pop
0020 putstring "bar"
0022 leave
I don't know how to execute the same script, by using the generated byte code.
Anyone please explain me how to execute this.
Thanks in advance!
TL;DR; You are looking for .eval
method.
The .compile
method would return an instance of RubyVM::InstructionSequence
class, which has .eval
method that evaluates/runs your "compiled" instructions.
iseq = RubyVM::InstructionSequence.compile("x = 50; x > 100 ? 'foo' : 'bar'")
iseq.eval # => "bar"
Or, a oneliner:
RubyVM::InstructionSequence.compile("x = 50; x > 100 ? 'foo' : 'bar'").eval