rl_lang/docs/entries/concepts/lambdas/
mod.rs

1use crate::docs::entry::{ConceptCategory, ConceptEntry, DescriptionEntry, DescriptionKind};
2
3pub static LAMBDAS: ConceptEntry = ConceptEntry {
4    name: "lambdas",
5    summary: "anonymous, inline functions that can capture their surrounding scope",
6    category: ConceptCategory::Functions,
7    prerequisites: &["functions", "variables", "types"],
8    descriptions: &[
9        DescriptionEntry {
10            kind: DescriptionKind::Explanation,
11            title: Some("defining a lambda"),
12            description: "lambdas are anonymous functions defined inline with `fn(<type> <param>, ...) { <body> }`",
13            examples: &[
14                "dec fn square = fn(int x) -> int {\n    return x * x\n}\n\nprintln(square(5))  // 25",
15            ],
16            expected_output: &["25"],
17        },
18        DescriptionEntry {
19            kind: DescriptionKind::Explanation,
20            title: Some("closures"),
21            description: "lambdas capture variables from their surrounding scope (closures)",
22            examples: &[
23                "dec int factor = 3\n\ndec fn triple = fn(int x) -> int {\n    return x * factor\n}\n\nprintln(triple(4))  // 12",
24            ],
25            expected_output: &["12"],
26        },
27        DescriptionEntry {
28            kind: DescriptionKind::Pitfall,
29            title: Some("captured values are snapshotted, not live"),
30            description: "a lambda captures the value of a variable at creation time - reassigning the outer variable afterward does not change what the lambda sees",
31            examples: &[
32                "dec int factor = 3\ndec fn triple = fn(int x) -> int {\n    return x * factor\n}\n\nfactor = 100\nprintln(triple(4))  // still 12, not 400",
33            ],
34            expected_output: &["12"],
35        },
36    ],
37    pitfalls: &["captured variables are snapshotted at creation, not live-referenced"],
38    related: &["functions", "closures"],
39    related_stdlib: &[],
40    since: None,
41};
rl_lang/docs/entries/concepts/lambdas/mod.rs

rl_lang/docs/entries/concepts/lambdas/
mod.rs
