From 144cabede201ace9507473a9c9a9200f475eec1a Mon Sep 17 00:00:00 2001 From: Kaz Kylheku Date: Mon, 29 Feb 2016 06:05:51 -0800 Subject: Implement @(next nil). * match.c (v_next): If argument to @(next) is nil, then evaluate remaining query in context with no list of files, and no data. * txr.1: Documented @(next nil). --- txr.1 | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'txr.1') diff --git a/txr.1 b/txr.1 index 3ece5efb..3b1bf55b 100644 --- a/txr.1 +++ b/txr.1 @@ -3163,6 +3163,7 @@ and takes various arguments, according to these possibilities: .mets @(next :env) .mets @(next :list << expr ) .mets @(next :string << expr ) +.mets @(next nil) .cble The lone @@ -3306,6 +3307,17 @@ the list which is not an empty input stream, but a stream consisting of one empty line. +The +.code @(next nil) +variant indicates that the following subquery is applied to empty data, +and the list of data sources from the command line is considered empty. +This directive is useful in front of \*(TX code which doesn't process data +sources from the command line, but takes command line arguments. +The +.code @(next nil) +incantation absolutely prevents \*(TX from trying to open the +first command line argument as a data source. + Note that the .code @(next) directive only redirect the source of input over the scope of subquery in which -- cgit v1.2.3