From 82f7268b2f7098442911a4b68d480a4791bd9e8f Mon Sep 17 00:00:00 2001 From: Oliver Reiche Date: Mon, 26 Sep 2022 10:52:39 +0200 Subject: Doc: Describe usage of 'env' expression --- doc/concepts/expressions.org | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'doc/concepts') diff --git a/doc/concepts/expressions.org b/doc/concepts/expressions.org index 2dff612a..d5d3340c 100644 --- a/doc/concepts/expressions.org +++ b/doc/concepts/expressions.org @@ -83,6 +83,16 @@ Finally, the ~"body"~ is evaluated in the final environemnt (after evaluating all binding entries) and the result of evaluating the ~"body"~ is the value for the whole ~"let*"~ expression. +***** Environment Map: ~"env"~ + +Creates a map from selected environment variables. + +The key ~"vars"~ (default ~[]~) has to be a list of literal strings referring to +the variable names that should be included in the produced map. This field is +not evaluated. This expression is only for convenience and does not give new +expression power. It is equivalent but lot shorter to multiple ~singleton_map~ +expressions combined with ~map_union~. + ***** Conditionals ****** Binary conditional: ~"if"~ -- cgit v1.2.3