Collections and iterators

Language reference for collections. Recipe-style walkthrough: Filter entity lists.

Vec and loops

let mut list: Vec<i64> = Vec::new();
list.push(1);
for item in list {
    // ...
}

Rust	Lua behaviour
Vec::new()	{}
push / len / is_empty	table.insert / # / # == 0
for x in v	ipairs(v) when v is typed Vec<_>; else unordered pairs(v)
for x in v.iter() / v.into_iter()	ordered ipairs(v)
for i in start..end	numeric for i = start, end - 1 do
for i in start..=end	numeric for i = start, end do

map / filter / collect

Supported: range or Vec iteration, then .map(|x| ...) and/or .filter(|x| ...), ending in .collect() / .collect::<Vec<_>>().

let mapped = (0..n).map(|i| i + 1).collect::<Vec<_>>();
let both = values
    .iter()
    .map(|i| i + 1)
    .filter(|i| *i > 1)
    .collect::<Vec<_>>();

Lowers to an immediately invoked Lua function that builds a table.

Not supported: enumerate, flat_map, zip, standing .iter() without collect, and arbitrary Iterator trait objects.

Related

• Type aliases - type Entities = Vec<_> still detects ipairs
• Supported Rust - full inventory