mike 5bfec20244 add match guards (#9621) ... ## description this pr adds [match guards](https://doc.rust-lang.org/reference/expressions/match-expr.html#match-guards) to match patterns ```nushell match $x { _ if $x starts-with 'nu' => {}, $x => {} } ``` these work pretty much like rust's match guards, with few limitations: 1. multiple matches using the `|` are not (yet?) supported ```nushell match $num { 0 | _ if (is-odd $num) => {}, _ => {} } ``` 2. blocks cannot be used as guards, (yet?) ```nushell match $num { $x if { $x ** $x == inf } => {}, _ => {} } ``` ## checklist - [x] syntax - [x] syntax highlighting[^1] - [x] semantics - [x] tests - [x] clean up [^1]: defered for another pr		2023-07-16 12:25:12 +12:00
..
core_commands	add match guards (#9621)	2023-07-16 12:25:12 +12:00
default_context.rs	Custom command input/output types (#9690)	2023-07-15 09:51:28 +12:00
example_support.rs	Apply nightly clippy lints (#9654)	2023-07-12 00:00:31 +02:00
example_test.rs	Test examples of use (#9032)	2023-06-25 07:43:48 -05:00
lib.rs	cratification: Example support (#8231)	2023-02-27 13:58:56 -08:00