[css-grid] Per WG resolution, explicitly disallow repeat() in grid-template.

Author: tabatkins

css-grid/Overview.bs

@@ -1200,17 +1200,18 @@ Explicit Track Sizing: the 'grid-template-rows' and 'grid-template-columns' prop
 
 	The syntax of a <a>track list</a> is:
 
-	<pre>
-		<dfn>&lt;track-list></dfn>         = [ <<line-names>>? [ <<track-size>> | <<track-repeat>> ] ]+ <<line-names>>?
-		<dfn>&lt;auto-track-list></dfn>    = [ <<line-names>>? [ <<fixed-size>> | <<fixed-repeat>> ] ]* <<line-names>>? <<auto-repeat>>
-		                       [ <<line-names>>? [ <<fixed-size>> | <<fixed-repeat>> ] ]* <<line-names>>?
-
-		<dfn>&lt;track-size></dfn>         = <<track-breadth>> | minmax( <<inflexible-breadth>> , <<track-breadth>> ) | fit-content( [ <<length>> | <<percentage>> ] )
-		<dfn>&lt;fixed-size></dfn>         = <<fixed-breadth>> | minmax( <<fixed-breadth>> , <<track-breadth>> ) | minmax( <<inflexible-breadth>> , <<fixed-breadth>> )
-		<dfn>&lt;track-breadth></dfn>      = <<length>> | <<percentage>> | <<flex>> | min-content | max-content | auto
-		<dfn>&lt;inflexible-breadth></dfn> = <<length>> | <<percentage>> | min-content | max-content | auto
-		<dfn>&lt;fixed-breadth></dfn>      = <<length>> | <<percentage>>
-		<dfn>&lt;line-names></dfn>         = '[' <<custom-ident>>* ']'
+	<pre class=prod>
+		<dfn>&lt;track-list></dfn>          = [ <<line-names>>? [ <<track-size>> | <<track-repeat>> ] ]+ <<line-names>>?
+		<dfn>&lt;auto-track-list></dfn>     = [ <<line-names>>? [ <<fixed-size>> | <<fixed-repeat>> ] ]* <<line-names>>? <<auto-repeat>>
+		                        [ <<line-names>>? [ <<fixed-size>> | <<fixed-repeat>> ] ]* <<line-names>>?
+		<dfn>&lt;explicit-track-list></dfn> = [ <<line-names>>? <<track-size>> ]+ <<line-names>>?
+
+		<dfn>&lt;track-size></dfn>          = <<track-breadth>> | minmax( <<inflexible-breadth>> , <<track-breadth>> ) | fit-content( [ <<length>> | <<percentage>> ] )
+		<dfn>&lt;fixed-size></dfn>          = <<fixed-breadth>> | minmax( <<fixed-breadth>> , <<track-breadth>> ) | minmax( <<inflexible-breadth>> , <<fixed-breadth>> )
+		<dfn>&lt;track-breadth></dfn>       = <<length>> | <<percentage>> | <<flex>> | min-content | max-content | auto
+		<dfn>&lt;inflexible-breadth></dfn>  = <<length>> | <<percentage>> | min-content | max-content | auto
+		<dfn>&lt;fixed-breadth></dfn>       = <<length>> | <<percentage>>
+		<dfn>&lt;line-names></dfn>          = '[' <<custom-ident>>* ']'
 	</pre>
 
 	Where:
@@ -1752,7 +1753,7 @@ Explicit Grid Shorthand: the 'grid-template' property</h3>
 	Name: grid-template
 	Value: none |
 	Value: <nobr>[ <<'grid-template-rows'>> / <<'grid-template-columns'>> ]</nobr> |
-	Value: <nobr>[ <<line-names>>? <<string>> <<track-size>>? <<line-names>>? ]+ [ / <<track-list>> ]?</nobr>
+	Value: <nobr>[ <<line-names>>? <<string>> <<track-size>>? <<line-names>>? ]+ [ / <<explicit-track-list>> ]?</nobr>
 	Initial: see individual properties
 	Applies to: <a>grid containers</a>
 	Inherited: see individual properties
@@ -1787,7 +1788,7 @@ Explicit Grid Shorthand: the 'grid-template' property</h3>
 				</pre>
 			</div>
 
-		<dt><dfn id='grid-template-ascii'>[ <<line-names>>? <<string>> <<track-size>>? <<line-names>>? ]+ [ / <<track-list>> ]?</dfn>
+		<dt><dfn id='grid-template-ascii'>[ <<line-names>>? <<string>> <<track-size>>? <<line-names>>? ]+ [ / <<explicit-track-list>> ]?</dfn>
 		<dd>
 			* Sets 'grid-template-areas' to the strings listed.
 			* Sets 'grid-template-rows' to the <<track-size>>s following each string
@@ -1835,6 +1836,9 @@ Explicit Grid Shorthand: the 'grid-template' property</h3>
 					</figcaption>
 				</figure>
 			</div>
+
+			Note: Note that the ''repeat()'' function isn't allowed in these track listings,
+			as the tracks are intended to visually line up one-to-one with the rows/columns in the “ASCII art”.
 	</dl>
 
 	Note: The 'grid' shorthand accepts the same syntax,