strings/in_place/changes.rb

tests/_examples/strings/in_place/changes.rb in the metorex repository.

# A String changes what it holds, and every reference to it sees the change.
held = "abc"
alias_of = held
held << "de"
held.concat "f", "g"
held << 33
p alias_of

held.replace "hello"
held.prepend "oh, "
held.insert 4, "!"
p held
p held.slice!(0, 5)
p held

p held.upcase!
p held.upcase!
p held.sub!("LLO", "y")
p held.reverse!
held.clear
p held

# A frozen String refuses every change.
settled = "kept".freeze
p settled.frozen?
begin
  settled << "more"
rescue FrozenError => problem
  p problem.message
end

# `+str` asks for one that changes and `-str` for one that does not.
p (+settled).frozen?
p (-"loose").frozen?

# Case mapping takes options.
p "CÅR".downcase(:ascii)
p "İ".downcase(:turkic)
p "ß".downcase(:fold)
p "ßet".capitalize

# A run of characters that are not letters or digits counts up as bytes.
p "(\xFF".succ.bytes

Output:

"abcdefg!"
"oh, !hello"
"oh, !"
"hello"
"HELLO"
nil
"HEy"
"yEH"
""
true
"can't modify frozen String: \"kept\""
false
true
"cÅr"
"i"
"ss"
"Sset"
[41, 0]