util.human.io.table: Allow a map callaback per column This allows e.g. mapping booleans to "yes" or "no", specific number formatting or generating virtual columns. All while not mutating the underlying data or creating additional temporary tables.

author: Kim Alvefur <zash@zash.se>
date: Thu, 04 Jun 2020 21:32:28 +0200
parent: 10910:e890b83f08cf
child: 10917:1eb83bc6f706
--- a/util/human/io.lua	Thu Jun 04 18:40:37 2020 +0200
+++ b/util/human/io.lua	Thu Jun 04 21:32:28 2020 +0200
@@ -131,7 +131,7 @@
 		local output = {};
 		for i, column in ipairs(col_specs) do
 			local width = widths[i];
-			local v = tostring(row[not titles and column.key or i] or "");
+			local v = (not titles and column.mapper or tostring)(row[not titles and column.key or i] or "", row);
 			if #v < width then
 				if column.align == "right" then
 					v = padleft(v, width-1).." ";