forked from extern/nushell
47 lines
936 B
Markdown
47 lines
936 B
Markdown
---
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title: reduce
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layout: command
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version: 0.59.0
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---
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Aggregate a list table to a single value using an accumulator block.
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## Signature
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```> reduce (block) --fold --numbered```
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## Parameters
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- `block`: reducing function
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- `--fold {any}`: reduce with initial value
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- `--numbered`: iterate with an index
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## Examples
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Sum values of a list (same as 'math sum')
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```shell
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> [ 1 2 3 4 ] | reduce {|it, acc| $it + $acc }
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```
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Sum values with a starting value (fold)
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```shell
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> [ 1 2 3 4 ] | reduce -f 10 {|it, acc| $acc + $it }
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```
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Replace selected characters in a string with 'X'
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```shell
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> [ i o t ] | reduce -f "Arthur, King of the Britons" {|it, acc| $acc | str find-replace -a $it "X" }
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```
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Find the longest string and its index
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```shell
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> [ one longest three bar ] | reduce -n { |it, acc|
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if ($it.item | str length) > ($acc | str length) {
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$it.item
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} else {
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$acc
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}
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}
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```
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