Primitives

Nim has several primitive types:

• signed integers: int8, int16, int32, int64, and int, where int is the same size as a pointer
• unsigned integers are similar with u prepended to the type
• floating points numbers: float32, float64, and float, where float is the processor’s fastest type
• characters: char, which is basically an alias for uint8

To indicate the size of an integer literal, append u or i and the size you’d like to the end. However, usually this is not necessary.

Integers can also have 0[xX], 0o, 0[Bb] prepended to indicate a hex, octal, or binary literal, respectively. Underscores are also valid in literals, and can help with readability.

let
  a: int8 = 0x7F # Works
  b: uint8 = 0b1111_1111 # Works
  d = 0xFF # type is int
  c: uint8 = 256 # Gets truncated to 0, 257 will be 1...

Precedence rules are the same as in most other languages, but instead of ^, &, |, >>, <<, the xor, and, or, shr, shl operators are used, respectively.

let
  a: int = 2
  b: int = 4
echo 4/2

$ nim c -r numbers2.nim
2.0

Another difference that may be surprising is that the / operator returns a floating point result, even when the operands are integers. If integer division is needed, the div operator should be used.