Dynamic arrays in Odin

[dynamic] grows on append and gives the memory back through delete.

package main

import "core:fmt"

main :: proc() {
    // [dynamic] grows on append; delete returns the memory.
    hauls: [dynamic]f32
    defer delete(hauls)

    append(&hauls, 12.5)
    append(&hauls, 8.0)
    append(&hauls, 15.25, 6.75)

    fmt.println(len(hauls), "hauls logged")
    fmt.printfln("first %.2f, last %.2f", hauls[0], hauls[len(hauls) - 1])
}

How it works

1. hauls: [dynamic]f32 starts empty; defer delete(hauls) schedules the cleanup.
2. append(&hauls, ...) takes a pointer and accepts several values at once.
3. len and indexing work like any array once the elements are in.

Keywords and builtins used here

• append
• defer
• delete
• dynamic
• f32
• import
• len
• package
• proc

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Step 2 of 3 in Collections, step 11 of 27 in Language basics.

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Dynamic arrays in other languages

• Delphi