nu_cmd_lang/core_commands/
module.rs1use nu_engine::command_prelude::*;
2use nu_protocol::engine::CommandType;
3
4#[derive(Clone)]
5pub struct Module;
6
7impl Command for Module {
8 fn name(&self) -> &str {
9 "module"
10 }
11
12 fn description(&self) -> &str {
13 "Define a custom module."
14 }
15
16 fn signature(&self) -> nu_protocol::Signature {
17 Signature::build("module")
18 .input_output_types(vec![(Type::Nothing, Type::Nothing)])
19 .allow_variants_without_examples(true)
20 .required("module", SyntaxShape::String, "Module name or module path.")
21 .optional(
22 "block",
23 SyntaxShape::Block,
24 "Body of the module if 'module' parameter is not a module path.",
25 )
26 .category(Category::Core)
27 }
28
29 fn extra_description(&self) -> &str {
30 r#"This command is a parser keyword. For details, check:
31 https://www.nushell.sh/book/thinking_in_nu.html"#
32 }
33
34 fn command_type(&self) -> CommandType {
35 CommandType::Keyword
36 }
37
38 fn run(
39 &self,
40 _engine_state: &EngineState,
41 _stack: &mut Stack,
42 _call: &Call,
43 _input: PipelineData,
44 ) -> Result<PipelineData, ShellError> {
45 Ok(PipelineData::empty())
46 }
47
48 fn examples(&self) -> Vec<Example<'_>> {
49 vec![
50 Example {
51 description: "Define a custom command in a module and call it",
52 example: r#"module spam { export def foo [] { "foo" } }; use spam foo; foo"#,
53 result: Some(Value::test_string("foo")),
54 },
55 Example {
56 description: "Define an environment variable in a module",
57 example: r#"module foo { export-env { $env.FOO = "BAZ" } }; use foo; $env.FOO"#,
58 result: Some(Value::test_string("BAZ")),
59 },
60 Example {
61 description: "Define a custom command that participates in the environment in a module and call it",
62 example: r#"module foo { export def --env bar [] { $env.FOO_BAR = "BAZ" } }; use foo bar; bar; $env.FOO_BAR"#,
63 result: Some(Value::test_string("BAZ")),
64 },
65 ]
66 }
67}