string - What does ?/ mean in Ruby? -

this question has answer here:

i stumbled across piece of code:

if source[0] != ?/   source = compute_asset_path(source, options) end

what's "?/"? i've never seen writing strings way.

$ irb 2.0.0p247 :001 > ?/ => "/"

apparently works single characters only:

2.0.0p247 :001 > ?a  => "a"  2.0.0p247 :002 > ?foo syntaxerror: (irb):2: syntax error, unexpected '?'

what ? mean?

? used represent single character string literals. ?a,?b not ?ab.

to answer comment of op :

yes, are.

irb(main):001:0> ?x + 'y' => "xy" irb(main):002:0> 'x' + 'y' => "xy"

Cap