7.7 KiB
Integers
Tomo has five types of integers:
Int: the default integer type, which uses an efficient tagged 29-bit integer value for small numbers, and falls back to a bigint implementation when values are too large to fit in 29-bits. The bigint implementation uses the GNU MP library. These integers are fast for small numbers and guaranteed to always be correct and never overflow.Int8/Int16/Int32/Int64: Fixed-size integers that take upNbits. These integers must be manually specified with their bits in square brackets (e.g.5[64]) and are subject to overflowing. If an overflow occurs, a runtime error will be raised.
Conversion between integer types can be done by calling the target type as a
function: Int32(x). For fixed-width types, the conversion function also
accepts a second parameter, truncate. If truncate is no (the default),
conversion will create a runtime error if the value is too large to fit in the
target type. If truncate is yes, then the resulting value will be a
truncated form of the input value.
Integers support the standard math operations (x+y, x-y, x*y, x/y) as
well as powers/exponentiation (x^y), modulus (x mod y and x mod1 y), and
bitwise operations: x and y, x or y, x xor y, x << y, and x >> y. The
operators and, or, and xor are bitwise, not logical operators.
Integer Functions
Each integer type has its own version of the following functions. Functions
can be called either on the type itself: Int.sqrt(x) or as a method call:
x:sqrt(). Method call syntax is preferred.
format
Description:
Formats an integer as a string with a specified number of digits.
Signature:
func format(i: Int, digits: Int = 0 -> Text)
Parameters:
i: The integer to be formatted.digits: The minimum number of digits to which the integer should be padded. Default is0.
Returns:
A string representation of the integer, padded to the specified number of digits.
Example:
>> 42:format(digits=5)
= "00042"
hex
Description:
Converts an integer to its hexadecimal representation.
Signature:
func hex(i: Int, digits: Int = 0, uppercase: Bool = yes, prefix: Bool = yes -> Text)
Parameters:
i: The integer to be converted.digits: The minimum number of digits in the output string. Default is0.uppercase: Whether to use uppercase letters for hexadecimal digits. Default isyes.prefix: Whether to include a "0x" prefix. Default isyes.
Returns:
The hexadecimal string representation of the integer.
Example:
>> 255:hex(digits=4, uppercase=yes, prefix=yes)
= "0x00FF"
octal
Description:
Converts an integer to its octal representation.
Signature:
func octal(i: Int, digits: Int = 0, prefix: Bool = yes -> Text)
Parameters:
i: The integer to be converted.digits: The minimum number of digits in the output string. Default is0.prefix: Whether to include a "0o" prefix. Default isyes.
Returns:
The octal string representation of the integer.
Example:
>> 64:octal(digits=4, prefix=yes)
= "0o0100"
random
Description:
Generates a random integer between the specified minimum and maximum values.
Signature:
func random(min: Int, max: Int -> Int)
Parameters:
min: The minimum value of the range.max: The maximum value of the range.
Returns:
A random integer between min and max (inclusive).
Example:
>> Int.random(1, 100)
= 47
from_text
Description:
Converts a text representation of an integer into an integer.
Signature:
func from_text(text: Text -> Int?)
Parameters:
text: The text containing the integer.
Returns:
The integer represented by the text. If the given text contains a value outside
of the representable range or if the entire text can't be parsed as an integer,
a null value will be returned.
Example:
>> Int.from_text("123")
= 123?
>> Int.from_text("0xFF")
= 255?
# Can't parse:
>> Int.from_text("asdf")
= !Int
# Outside valid range:
>> Int8.from_text("9999999")
= !Int
to
Description:
Creates an inclusive range of integers between the specified start and end values.
Signature:
func to(from: Int, to: Int -> Range)
Parameters:
from: The starting value of the range.to: The ending value of the range.
Returns:
A range object representing all integers from from to to (inclusive).
Example:
>> 1:to(5)
= Range(first=1, last=5, step=1)
abs
Description:
Calculates the absolute value of an integer.
Signature:
func abs(x: Int -> Int)
Parameters:
x: The integer whose absolute value is to be calculated.
Returns:
The absolute value of x.
Example:
>> -10:abs()
= 10
sqrt
Description:
Calculates the square root of an integer.
Signature:
func sqrt(x: Int -> Int)
Parameters:
x: The integer whose square root is to be calculated.
Returns:
The integer part of the square root of x.
Example:
>> 16:sqrt()
= 4
>> 17:sqrt()
= 4
is_prime
Description:
Determines if an integer is a prime number.
Note: This function is probabilistic. With the default arguments, the chances of getting an incorrect answer are astronomically small (on the order of 10^(-30)). See the GNU MP docs for more details.
Signature:
func is_prime(x: Int, reps: Int = 50 -> Bool)
Parameters:
x: The integer to be checked.reps: The number of repetitions for primality tests. Default is50.
Returns:
yes if x is a prime number, no otherwise.
Example:
>> 7:is_prime()
= yes
>> 6:is_prime()
= no
next_prime
Description:
Finds the next prime number greater than the given integer.
Note: This function is probabilistic, but the chances of getting an incorrect answer are astronomically small (on the order of 10^(-30)). See the GNU MP docs for more details.
Signature:
func next_prime(x: Int -> Int)
Parameters:
x: The integer after which to find the next prime.
Returns:
The next prime number greater than x.
Example:
>> 11:next_prime()
= 13
prev_prime
Description:
Finds the previous prime number less than the given integer.
If there is no previous prime number (i.e. if a number less than 2 is
provided), then the function will create a runtime error.
Note: This function is probabilistic, but the chances of getting an incorrect answer are astronomically small (on the order of 10^(-30)). See the GNU MP docs for more details.
Signature:
func prev_prime(x: Int -> Int)
Parameters:
x: The integer before which to find the previous prime.
Returns:
The previous prime number less than x.
Example:
>> 11:prev_prime()
= 7
clamped
Description:
Returns the given number clamped between two values so that it is within
that range.
Signature:
func clamped(x, low, high: Int -> Int)
Parameters:
x: The integer to clamp.low: The lowest value the result can take.high: The highest value the result can take.
Returns:
The first argument clamped between the other two arguments.
Example:
>> 2:clamped(5, 10)
= 5