= Numeric operations

== Arithmetic operators

The usual arithmetic operators are provided.

[source]
.Example
....
nix-repl> 1 + 2   # addition
3

nix-repl> 5 - 3   # subtraction
2

nix-repl> 3 * 4   # multiplication
12

nix-repl> 6 / 2   # division
3

nix-repl> -1      # negation
-1
....

[IMPORTANT]
====
As mentioned in <<_variables>>,
you can get unexpected results when you omit spaces around operators.
Consider the following example.

[source]
.Example
....
nix-repl> 6/2
/home/amy/codeberg/nix-book/6/2
....

What happened?
Let's use the `:t` command to find out the type of the expression.

[source]
.Example
....
nix-repl> :t 6/2
a path
....

If an expression can be interpreted as a path, Nix will do so.
This is useful, because paths are _far_ more commonly used in Nix expressions
than arithmetic operators.
In this case, Nix interpreted `6/2` as a relative path from the current directory,
which in the above example was `/home/amy/codeberg/nix-book`.

Adding a space after the `/` operator produces the expected result.

[source]
.Example
....
nix-repl> 6/ 2
3
....

To avoid surprises and improve readability, I prefer to use spaces before and after all operators.
====

== Floating-point calculations

Numbers without a decimal point are assumed to be integers.
To ensure that a number is interpreted as a floating-point value, add a decimal point.

[source]
.Example
....
nix-repl> :t 5
an integer

nix-repl> :t 5.0
a float

nix-repl> :t 5.
a float
....

In the example below, the first expression results in integer division (rounding down),
while the second produces a floating-point result.

[source]
.Example
....
nix-repl> 5 / 3
1

nix-repl> 5.0 / 3
1.66667
....