---
layout: default
title: Examples
---

## Types of Expressions

- function definition Expressions
  - macro define Expressions -> core library function
  - anonymous function defines -> `() {}` that can be assigned
  - lambda function defines -> `[]() {}`
- class definition Expressions -> `class ident() {}`
- data definition Expressions -> `data ident {}`
- variable definition Expressions -> `let ident = expr`, `const ident = expr`
- variable redefinition Expressions -> `ident = expr`

<!-- ? Maybe not actually -->
<!-- - operator Expressions -> `expr op expr`, `ident op expr`, `expr op ident` based on l/r-value semantics -->

## Types of expressions

Most things are an expression like rust. Expressions evaluate to a value like an expression, but does not return it. Instead it prob assigns it.

But unlike rust we dont have semicolons and instead rely on whitespace (default style = 2 spaces of inlining, 1 space between clauses). We need a clear way of distinguishing between expressions and Expressions.

So rei's keywords and design allows us to separate between them. Cues like `let` should delineate a statement. All expressions evaluate to a value.