Parser

The parser converts tokens into an AST.

This process is called syntactic analysis.

For:

let x = 10

the parser creates a structure equivalent to:

VariableDeclaration
├── name: x
└── initializer: 10

Expression precedence

The parser uses precedence levels:

assignment
    ↓
logical OR
    ↓
logical AND
    ↓
equality
    ↓
comparison
    ↓
term
    ↓
factor
    ↓
unary
    ↓
call
    ↓
primary

For:

a + b * 2

the parser produces:

      +
     /     a   *
       /       b   2

rather than:

      *
     /     +   2
   /   a   b

So the expression means:

a + (b * 2)