builtins/pack_and_trace.rb

tests/_examples/builtins/pack_and_trace.rb in the metorex repository.

# The directive machine `pack` writes with and `unpack` reads back.
p [65, 66, 67].pack("C*")
p "abc".unpack("C*")
p "abc".unpack("C2")
p "ab".unpack("v")
p "ab".unpack("n")
p "ab".unpack("S<")
p "ab".unpack("S>")
p "abcdefgh".unpack("Q<")
p ["ab"].pack("a4").length
p ["ab"].pack("A4")
p "abc\x00def".unpack("Z*Z*")
p "\x80".unpack("B*")
p "\x8f".unpack("H2")
p [300].pack("w").length
p "abc".unpack1("C")
p "abcd".unpack("C3X*C")
p [1].pack("l!").length
p [1].pack("i!").length

# A character named by an escape.
p ?\001
p ?\n
p ?\x41

# A trace is handed each event it asked for.
seen = []
tracer = TracePoint.new(:line) { |point| seen.push [point.event, point.lineno] }
p tracer.enabled?
tracer.enable
answer = 1
tracer.disable
p tracer.enabled?
p seen.length
p seen.first[0]

calls = []
def traced_method
  7
end
watcher = TracePoint.new(:call, :return) { |point| calls.push [point.event, point.method_id] }
watcher.enable { traced_method }
p calls

p Marshal::MAJOR_VERSION
p Marshal::MINOR_VERSION
walk = 1.upto("A")
p walk.class
begin
  walk.size
rescue ArgumentError => problem
  p problem.message
end
p 5.upto(10).size

Output:

"ABC"
[97, 98, 99]
[97, 98]
[25185]
[24930]
[25185]
[24930]
[7523094288207667809]
4
"ab  "
["abc", "def"]
["10000000"]
["8f"]
2
97
[97, 98, 99, 99]
8
4
"\u0001"
"\n"
"A"
false
false
2
:line
[[:call, :traced_method], [:return, :traced_method]]
4
8
Enumerator
"comparison of Integer with \"A\" failed"
6