Range Operator: ~

Overview

The tilde operator ~ defines ranges in Linea v4.1. It's used primarily in for loops for clean, readable iteration.

Basic Syntax

start~end
start~end step increment

Inclusive Ranges

The ~ operator creates inclusive ranges (both endpoints included):

Simple Range

for i from 1~5 {
    display i
}
// Output: 1, 2, 3, 4, 5

Range from 0

for i from 0~10 {
    display i
}
// Output: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

Step Values

Positive Step (Skip Forward)

for i from 0~20 step 5 {
    display i
}
// Output: 0, 5, 10, 15, 20

Negative Step (Backward)

for i from 10~1 step -1 {
    display i
}
// Output: 10, 9, 8, 7, 6, 5, 4, 3, 2, 1

Large Steps

for i from 0~100 step 10 {
    display i
}
// Output: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100

Dynamic Ranges

Use variables for start and end points:

var start @ int = 5
var end @ int = 15
for i from start~end {
    display i
}

Array Iteration

Using Array Length

var arr @ [int] = [10, 20, 30, 40]
var n @ int = len(arr)
for i from 0~(n-1) {
    display arr[i]
}

Reverse Array Iteration

var arr @ [int] = [1, 2, 3, 4]
for i from 3~0 step -1 {
    display arr[i]
}
// Output: 4, 3, 2, 1

Common Patterns

var a @ int = 0
var b @ int = 1
for i from 0~9 {
    display a
    var temp @ int = a + b
    a = b
    b = temp
}

var n @ int = 5
for i from 1~10 {
    display n * i
}

Differences from Other Languages

Performance Considerations

• Ranges are compiled efficiently: No runtime overhead
• Positive steps: Compiled to Rust's optimized ranges
• Negative steps: Use while loops internally
• Cache locality: Better performance with sequential access