= If expressions

The conditional construct in Nix is an _expression_, not a _statement_.
Since expressions must have values in all cases, you must specify both the `then` and the `else` branch.

[source]
.Example
....
nix-repl> a = 7

nix-repl> b = 3

nix-repl> if a > b then "yes" else "no"
"yes"
....

