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Class type
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Tablecloth.Int
SourceThe platform-dependant signed integer type. An int
is a whole number. Valid syntax for int
s includes:
0
42
9000
1_000_000
1_000_000
0xFF (* 255 in hexadecimal *)
0x000A (* 10 in hexadecimal *)
Note: The number of bits used for an int
is platform dependent.
When targeting native OCaml uses 31-bits on a 32-bit platforms and 63-bits on a 64-bit platforms which means that int
math is well-defined in the range -2 ** 30
to 2 ** 30 - 1
for 32bit platforms -2 ** 62
to 2 ** 62 - 1
for 64bit platforms.
You can read about the reasons for OCamls unusual integer sizes here.
When targeting JavaScript, that range is -2 ** 53
to 2 ** 53 - 1
.
Outside of that range, the behavior is determined by the compilation target.
int
s are subject to overflow, meaning that Int.maximumValue + 1 = Int.minimumValue
.
Historical Note: The name int
comes from the term integer). It appears that the int
abbreviation was introduced in the programming language ALGOL 68.
Today, almost all programming languages use this abbreviation.
Note You do not need to open the Int
module to use the (+)
, (-)
, (*)
or (/)
operators, these are available as soon as you open Tablecloth
Subtract numbers
Int.subtract 4 3 = 1
Alternatively the operator can be used:
4 - 3 = 1
See Int.subtract
Multiply int
s like
Int.multiply 2 7 = 14
Alternatively the operator can be used:
(2 * 7) = 14
See Int.multiply
Integer division:
Int.divide 3 ~by:2 = 1
27 / 5 = 5
Notice that the remainder is discarded.
Throws Division_by_zero
when the by
(the divisor) is 0
.
See Int.divide
Exponentiation, takes the base first, then the exponent.
Int.power ~base:7 ~exponent:3 = 343
Alternatively the **
operator can be used:
7 ** 3 = 343
Flips the 'sign' of an integer so that positive integers become negative and negative integers become positive. Zero stays as it is.
Int.negate 8 = (-8)
Int.negate (-7) = 7
Int.negate 0 = 0
Alternatively the operator can be used:
~-(7) = (-7)
See Int.negate
Perform modular arithmetic.
If you intend to use modulo
to detect even and odd numbers consider using Int.isEven
or Int.isOdd
.
Int.modulo ~by:2 0 = 0
Int.modulo ~by:2 1 = 1
Int.modulo ~by:2 2 = 0
Int.modulo ~by:2 3 = 1
Our modulo
function works in the typical mathematical way when you run into negative numbers:
List.map ~f:(Int.modulo ~by:4) [(-5); (-4); -3; -2; -1; 0; 1; 2; 3; 4; 5 ] =
[3; 0; 1; 2; 3; 0; 1; 2; 3; 0; 1]
Use Int.remainder
for a different treatment of negative numbers.
Get the remainder after division. Here are bunch of examples of dividing by four:
List.map ~f:(Int.remainder ~by:4) [(-5); (-4); (-3); (-2); (-1); 0; 1; 2; 3; 4; 5] =
[(-1); 0; (-3); (-2); (-1); 0; 1; 2; 3; 0; 1]
Use Int.modulo
for a different treatment of negative numbers.
Returns the larger of two int
s
Int.maximum 7 9 = 9
Int.maximum (-4) (-1) = (-1)
Returns the smaller of two int
s
Int.minimum 7 9 = 7
Int.minimum (-4) (-1) = (-4)
Check if an int
is even
Int.isEven 8 = true
Int.isEven 7 = false
Int.isEven 0 = true
Check if an int
is odd
Int.isOdd 7 = true
Int.isOdd 8 = false
Int.isOdd 0 = false
Clamps n
within the inclusive lower
and upper
bounds.
Int.clamp ~lower:0 ~upper:8 5 = 5
Int.clamp ~lower:0 ~upper:8 9 = 8
Int.clamp ~lower:(-10) ~upper:(-5) 5 = (-5)
Throws an Invalid_argument
exception if lower > upper
Checks if n
is between lower
and up to, but not including, upper
.
Int.inRange ~lower:2 ~upper:4 3 = true
Int.inRange ~lower:5 ~upper:8 4 = false
Int.inRange ~lower:(-6) ~upper:(-2) (-3) = true
Throws an Invalid_argument
exception if lower > upper
Convert an int
into a string
representation.
Int.toString 3 = "3"
Int.toString (-3) = "-3"
Int.toString 0 = "0"
Guarantees that
Int.(fromString (toString n)) = Some n
Attempt to parse a string
into a int
.
Int.fromString "0" = Some 0.
Int.fromString "42" = Some 42.
Int.fromString "-3" = Some (-3)
Int.fromString "123_456" = Some 123_456
Int.fromString "0xFF" = Some 255
Int.fromString "0x00A" = Some 10
Int.fromString "Infinity" = None
Int.fromString "NaN" = None