src/location: add doc to `Location::column_start`

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/src/location.nit b/src/location.nit
index 8ed4428..e82775a 100644 (file)
--- a/src/location.nit
+++ b/src/location.nit
@@ -54,7 +54,16 @@ class Location
        var file: nullable SourceFile
        var line_start: Int
        var line_end: Int
+
+       # Start of this location on `line_start`
+       #
+       # A `column_start` of 1 means the first column or character.
+       #
+       # If `column_start == 0` this location concerns the whole line.
+       #
+       # Require: `column_start >= 0`
        var column_start: Int
+
        var column_end: Int
 
        # The index in the start character in the source