Add syntax highlighting

NEWS.md

@@ -1,6 +1,10 @@
 # Genoa Banner Creator project news
 
-## [0.5 alpha] - unreleased
+## [0.5 alpha] - 2023-09-15
+
+### Added
+
+* Syntax highlighting and line numbers
 
 ### Changed
 

README.md

@@ -15,7 +15,7 @@ As of September 2023, Genoa is at a very early alpha stage: incomplete, poorly d
 
 ## Usage
 
-Genoa is powered by a little language based on Tcl. For example its own promotional banner is defined like this:
+Genoa is powered by a little language based on Tcl. For example its own promotional cover is defined like this:
 
 ```tcl
 # The viewport declaration can be anywhere.

genoa.tcl

@@ -24,12 +24,13 @@
 package require Tcl 8.6
 package require Tk 8.6
 
+package require ctext
 package require getstring
 namespace import getstring::*
 
 set window_title "Genoa Banner Creator"
 
-set about_text "Tool to Generate Original Art\nv0.4 alpha (14 Sep 2023)"
+set about_text "Tool to Generate Original Art\nv0.5 alpha (15 Sep 2023)"
 set credits_text "Made by No Time To Play\nMIT License"
 set site_link "https://notimetoplay.org/graphics/genoa/"
 
@@ -312,7 +313,7 @@ ttk::frame .workspace.view
 .workspace add .workspace.edit -weight 1
 .workspace add .workspace.view -weight 1
 
-set editor [text .workspace.edit.text \
+set editor [ctext .workspace.edit.text \
 	-width 40 -height 25 -wrap "word" -undo 1]
 font_size::reset $editor
 tk_util::pack_scrolled $editor
@@ -470,6 +471,18 @@ if {[llength [info commands "console"]] > 0} {
 	bind . <Command-l> {console show}
 }
 
+ctext::addHighlightClass $editor statements blue \
+	"proc set incr if else for foreach while switch break continue return repeat alert"
+ctext::addHighlightClass $editor functions purple \
+	"expr list string length llength + - * / sin cos"
+ctext::addHighlightClass $editor drawing purple \
+	"line box circle oval text polygon color fill width font size viewport"
+ctext::addHighlightClassWithOnlyCharStart $editor variables fuchsia "\$"
+ctext::addHighlightClassForSpecialChars $editor punctuation blue {[]{};}
+ctext::addHighlightClassForRegexp $editor comments gray {#[^\n\r]*}
+ctext::addHighlightClassForRegexp $editor numbers green {[0-9\.\-]+}
+ctext::addHighlightClassForRegexp $editor strings green {".*?"}
+
 proc show_modified {} {
 	global status editor
 	if {[$editor edit modified]} {
@@ -537,6 +550,7 @@ proc load_file full_path {
 	try {
 		set f [open $full_path]
 		tk_util::load_text $editor [read $f]
+		$editor highlight 1.0 end
 		set status "Opened $fn"
 		wm title . "$fn | $window_title"
 		return 1