extern/nushell
1
0
Fork 1
mirror of https://github.com/nushell/nushell.git synced 2024-11-22 00:13:21 +01:00
Code Issues Packages Projects Releases Wiki Activity

Tiny make up to the documentation of reduce (#13408)

Browse Source 
This tiny PR improves the documentation of the `reduce` command by
explicitly stating the direction of reduction, i.e. from left to right,
and adds an example for demonstration.


---------

Co-authored-by: Ben Yang <ben@ya.ng>
This commit is contained in:
suimong 2024-07-20 01:55:38 +08:00 committed by GitHub
parent aa9a42776b
commit dbd60ed4f4
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
crates/nu-command/src/filters/reduce.rs
View File

@ -36,7 +36,7 @@ impl Command for Reduce {
}
fn usage(&self) -> &str {
"Aggregate a list to a single value using an accumulator closure."
"Aggregate a list (starting from the left) to a single value using an accumulator closure."
}
fn search_terms(&self) -> Vec<&str> {
@ -50,6 +50,11 @@ impl Command for Reduce {
description: "Sum values of a list (same as 'math sum')",
result: Some(Value::test_int(10)),
},
Example {
example: "[ 1 2 3 4 ] | reduce {|it, acc| $acc - $it }",
description: r#"`reduce` accumulates value from left to right, equivalent to (((1 - 2) - 3) - 4)."#,
result: Some(Value::test_int(-8)),
},
Example {
example:
"[ 8 7 6 ] | enumerate | reduce --fold 0 {|it, acc| $acc + $it.item + $it.index }",
@ -61,6 +66,11 @@ impl Command for Reduce {
description: "Sum values with a starting value (fold)",
result: Some(Value::test_int(20)),
},
Example {
example: r#"[[foo baz] [baz quux]] | reduce --fold "foobar" {|it, acc| $acc | str replace $it.0 $it.1}"#,
description: "Iteratively perform string replace (from left to right): 'foobar' -> 'bazbar' -> 'quuxbar'",
result: Some(Value::test_string("quuxbar")),
},
Example {
example: r#"[ i o t ] | reduce --fold "Arthur, King of the Britons" {|it, acc| $acc | str replace --all $it "X" }"#,
description: "Replace selected characters in a string with 'X'",