readln() returns new line charater

[Jakob Ovrum]

On Saturday, 28 December 2013 at 17:23:30 UTC, Jeroen Bollen 
wrote:
> Usually if you're working with a console though the input 
> stream won't exhaust and thus the blocking 'readln' would be a 
> better option, no?

The blocking behaviour of `stdin` by default is fine. The issue 
is that `readln` returns an empty string when `stdin` is 
empty/closed, which is different from an empty line (which is 
just the line terminator). Approaches that erase the difference 
with functions like `chomp` can't tell them apart.

Assuming that `stdin` will never close seems like a bad idea when 
it's so easy to handle, and the consequences of it closing can be 
harsh (particularly an infinite loop). Even assuming that `stdin` 
will never be redirected and always used from a console, an 
experienced user might use ^Z to close standard input to signal a 
clean end, only to be faced with either an obscure error, 
segfault or infinite loop.