Find the larger of two comparables.

Find the smaller of two comparables.

Represents the relative ordering of two things. The relations are less than, equal to, and greater than.

Compare any two comparable values. Comparable values include String, Char, Int, Float, Time, or a list or tuple containing comparable values. These are also the only values that work as Dict keys or Set members.

Negate a boolean value.

not True == False
not False == True

The logical AND operator. True if both inputs are True. This operator short-circuits to False if the first argument is False.

The logical OR operator. True if one or both inputs are True. This operator short-circuits to True if the first argument is True.

The exclusive-or operator. True if exactly one input is True.

Floating point division.

Exponentiation

3^2 == 9

Integer division. The remainder is discarded.

Find the remainder after dividing one number by another.

 7 `rem` 2 == 1
-1 `rem` 4 == -1

Perform modular arithmetic.

 7 % 2 == 1
-1 % 4 == 3

Negate a number.

negate 42 == -42
negate -42 == 42
negate 0 == 0

Take the absolute value of a number.

Take the square root of a number.

Clamps a number within a given range. With the expression clamp 100 200 x the results are as follows:

100     if x < 100
 x      if 100 <= x < 200
200     if 200 <= x

Calculate the logarithm of a number with a given base.

logBase 10 100 == 2
logBase 2 256 == 8

An approximation of e.

An approximation of pi.

You probably do not want to use this. It takes (y/x) as the argument, so there is no way to know whether the negative signs comes from the y or x. Thus, the resulting angle is always between π/2 and -π/2 (in quadrants I and IV). You probably want to use atan2 instead.

This helps you find the angle of a Cartesian coordinate. You will almost certainly want to use this instead of atan. So atan2 y x computes atan(y/x) but also keeps track of which quadrant the angle should really be in. The result will be between π and -π, giving you the full range of angles.

Round a number to the nearest integer.

Floor function, rounding down.

Ceiling function, rounding up.

Truncate a number, rounding towards zero.

Convert an integer into a float.

Convert degrees to standard Elm angles (radians).

Convert radians to standard Elm angles (radians).

Convert turns to standard Elm angles (radians). One turn is equal to 360°.

Convert Cartesian coordinates (x,y) to polar coordinates (r,θ).

Convert polar coordinates (r,θ) to Cartesian coordinates (x,y).

Determine whether a float is an undefined or unrepresentable number. NaN stands for not a number and it is a standardized part of floating point numbers.

isNaN (0/0)     == True
isNaN (sqrt -1) == True
isNaN (1/0)     == False  -- infinity is a number
isNaN 1         == False

Determine whether a float is positive or negative infinity.

isInfinite (0/0)     == False
isInfinite (sqrt -1) == False
isInfinite (1/0)     == True
isInfinite 1         == False

Notice that NaN is not infinite! For float n to be finite implies that not (isInfinite n || isNaN n) evaluates to True.

Turn any kind of value into a string. When you view the resulting string with Text.fromString it should look just like the value it came from.

toString 42 == "42"
toString [1,2] == "[1,2]"
toString "he said, \"hi\"" == "\"he said, \\\"hi\\\"\""

Put two appendable things together. This includes strings, lists, and text.

"hello" ++ "world" == "helloworld"
[1,1,2] ++ [3,5,8] == [1,1,2,3,5,8]

Given a 2-tuple, returns the first value.

Given a 2-tuple, returns the second value.

Given a value, returns exactly the same value. This is called the identity function.

Create a constant function, a function that always returns the same value regardless of what input you give. It is defined as:

always a b = a

It totally ignores the second argument, so always 42 is a function that always returns 42. When you are dealing with higher-order functions, this comes in handy more often than you might expect. For example, creating a zeroed out list of length ten would be:

map (always 0) [0..9]

Backward function application f <| x == f x. This function is useful for avoiding parenthesis. Consider the following code to create a text element:

leftAligned (monospace (fromString "code"))

This can also be written as:

leftAligned << monospace <| fromString "code"

Forward function application x |> f == f x. This function is useful for avoiding parenthesis and writing code in a more natural way. Consider the following code to create a pentagon:

scale 2 (move (10,10) (filled blue (ngon 5 30)))

This can also be written as:

ngon 5 30
  |> filled blue
  |> move (10,10)
  |> scale 2

Function composition, passing results along in the suggested direction. For example, the following code checks if the square root of a number is odd:

not << isEven << sqrt

You can think of this operator as equivalent to the following:

(g << f)  ==  (\x -> g (f x))

So our example expands out to something like this:

\n -> not (isEven (sqrt n))

Function composition, passing results along in the suggested direction. For example, the following code checks if the square root of a number is odd:

sqrt >> isEven >> not

This direction of function composition seems less pleasant than (<<) which reads nicely in expressions like: filter (not << isRegistered) students

Flip the order of the first two arguments to a function.

Change how arguments are passed to a function. This splits paired arguments into two separate arguments.

Change how arguments are passed to a function. This combines two arguments into a single pair.