ruby - Some code that I don't understand -


i don't understand while true, name = gets(',').chomp(',') , relationship. me, seems infinite loop. explain this?

 print "enter more names separated commas: "  while true    name = gets(',').chomp(',')    puts "hello #{name}"  end

it is infinite loop. program never end (except crash on input). breaking down:

while true

this start while loop condition true loop forever on code end.

name = gets(',')

see documentation gets. if run program directly, wait "line" of input on stdin (the console/terminal). input read record separator, "," , result assigned variable name.

.chomp(',')

chomp method on string removes record separator end of string (again, ',' in case).

puts "hello #{name}"

this prints string "hello #{name}" value of name variable interpolated #{} placeholder.

end

this ends while loop.

if run program , type "mary, angela, andy" , press enter will:

  1. read "mary," stdin, chomp "," off end, , assign "mary" name variable.
  2. print "hello mary" stdout.
  3. loop top, read "angela,", etc...
  4. loop top, , wait because there not record separator on stdin.

if type "foo," , press enter, will:

  1. read "andy\nfoo," stdin, chomp "," off end, etc...
  2. print "hello andy\nfoo" stdout

so pretty lousy program given ostensibly trying do, there have it.


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