nu_command/math/
product.rs

1use crate::math::{
2    reducers::{Reduce, reducer_for},
3    utils::run_with_function,
4};
5use nu_engine::command_prelude::*;
6
7#[derive(Clone)]
8pub struct MathProduct;
9
10impl Command for MathProduct {
11    fn name(&self) -> &str {
12        "math product"
13    }
14
15    fn signature(&self) -> Signature {
16        Signature::build("math product")
17            .input_output_types(vec![
18                (Type::List(Box::new(Type::Number)), Type::Number),
19                (Type::Range, Type::Number),
20                (Type::table(), Type::record()),
21                (Type::record(), Type::record()),
22            ])
23            .allow_variants_without_examples(true)
24            .category(Category::Math)
25    }
26
27    fn description(&self) -> &str {
28        "Returns the product of a list of numbers or the products of each column of a table."
29    }
30
31    fn search_terms(&self) -> Vec<&str> {
32        vec!["times", "multiply", "x", "*"]
33    }
34
35    fn is_const(&self) -> bool {
36        true
37    }
38
39    fn run(
40        &self,
41        _engine_state: &EngineState,
42        _stack: &mut Stack,
43        call: &Call,
44        input: PipelineData,
45    ) -> Result<PipelineData, ShellError> {
46        run_with_function(call, input, product)
47    }
48
49    fn run_const(
50        &self,
51        _working_set: &StateWorkingSet,
52        call: &Call,
53        input: PipelineData,
54    ) -> Result<PipelineData, ShellError> {
55        run_with_function(call, input, product)
56    }
57
58    fn examples(&self) -> Vec<Example<'_>> {
59        vec![
60            Example {
61                description: "Compute the product of a list of numbers",
62                example: "[2 3 3 4] | math product",
63                result: Some(Value::test_int(72)),
64            },
65            Example {
66                description: "Compute the product of each column in a table",
67                example: "[[a b]; [1 2] [3 4]] | math product",
68                result: Some(Value::test_record(record! {
69                    "a" => Value::test_int(3),
70                    "b" => Value::test_int(8),
71                })),
72            },
73        ]
74    }
75}
76
77/// Calculate product of given values
78pub fn product(values: &[Value], span: Span, head: Span) -> Result<Value, ShellError> {
79    let product_func = reducer_for(Reduce::Product);
80    product_func(Value::nothing(head), values.to_vec(), span, head)
81}
82
83#[cfg(test)]
84mod test {
85    use super::*;
86
87    #[test]
88    fn test_examples() {
89        use crate::test_examples;
90
91        test_examples(MathProduct {})
92    }
93}
nu_command/math/product.rs

nu_command/math/
product.rs
