_Expr_ is a GO package capable of analysing, interpreting and calculating expressions.
=== Data types
_Expr_ supports numerical, string, relational, and boolean expressions.
==== Numbers
Numbers can be integers (GO int64) and float (GO float64). In mixed operations involving integers and floats, integers are automatically promoted to floats.
.Arithmetic operators
[cols="1,2,4,4"]
|===
| Symbol | Operation | Description | Examples
| `+` / `-` | _change sign_ | Change the sign of values | `-1` [-1], `-(+2)` [-2]