Answers for "php is false"

php is string

is_string($var)

true false php

""         -> false
"0"        -> false
"0.0"      -> true
"1"        -> true
"01"       -> true
"abc"      -> true
"true"     -> true
"false"    -> true
"null"     -> true
0          -> false
0.1        -> true
1          -> true
1.1        -> true
-42        -> true
"NAN"      -> true
0          -> false
NAN        -> true
null       -> false
true       -> true
false      -> false
[]         -> false
[""]       -> true
["0"]      -> true
[0]        -> true
[null]     -> true
["a"]      -> true
{}         -> true
{}         -> true
{"t":"s"}  -> true
{"c":null} -> true