== Extending tcl to generate html ==

[CMcC] Following from [jenglish]'s comment: why learn to use a monster HTML-template library when you can, with a few lines of code, extend the base language so you can write things like [[<A> href "/home.html" { ! "Home" }]] ... I wrote the following to do just that using the techniques in [let unknown know].

 package require know
 know {[string match <*> [lindex $args 0]]} {
    set tag [string trim [lindex $args 0] "<>"]
    ::proc ::<$tag> {args} [string map [list @T $tag] {
	set result {}
	foreach {n v} [lrange $args 0 end-1] {
	    lappend result "$n='[armour $v]'"
	}
	return "<@T [join ${result}]>[lindex $args end]</@T>"
    }]
    return [eval $args]
 }

This will generate a proc for any command like [[<li>]] which will do pretty much what you'd expect it to.

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== Armouring HTML ==

Prevent output from containing html-significant characters

 interp alias {} armour {} string map {& & < < > > \" " ' '} ... fairly clearly ''that'' needs some work :)

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== Looping in HTML generation ==

Often what you want isn't to loop, but to convert a list into something else.  One generic technique I've found helpful is the use of [join], as follows:

  <ul><li>[[join $list </li></li>]</li></ul>

Which will convert a tcl list into an HTML unordered list.  Similar techniques are possible with <table>s