Integer literals



print(255)        // decimal literal
print(0000'00FF)  // hexadecimal literal
print(00'FF)      // short hexadecimal literal
print(F'F)        // ultrashort (single-byte) hexadecimal literal
print(377o)       // octal literal
print(1111'1111b) // binary literal
print(255'000)    // decimal literal
Output:
255
255
255
255
255
255
255000

Note that digit separator 
'
is necessary for hexadecimal literals.
[Someone might want to put in code a credit card number (like 1234'5678'9012'3456, which is hexadecimal (but not decimal!) literal in 11l), but how frequently this is really needed in practice?]

Why 
'
instead of 
_
— there may be a valid variable name (e.g. 
FFFF_FFFF
or 
C0_DE
).