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The oo::dialect Package
=======================
*oo::dialect* is designed for building TclOO based domain specific languages. It does this
by providing:
* a meta class
* a core object
* A namespace in which to define additional keywords
* A "define" command to mirror the capabilties of *oo::define*
Example usage:
<pre>
<code>
package require oo::dialect
oo::dialect::create tool
# Add a new keyword
proc ::tool::define::option {name def} {
set class [class_current]
oo::meta::info $class branchset option $name $def
}
# Override the "constructor" keyword
proc ::tool::define::constructor {arglist body} {
set class [class_current]
set prebody {
my _optionInit
}
oo::define $class constructor $arglist "$prebody\n$body"
}
# Add functions to the core class
::tool::define ::tool::object {
method _optionInit {} {
my variable options
foreach {opt info} [my meta getnull option] {
set options($opt) [dict getnull $info default:]
}
}
method cget option {
my variable options
return $options($option)
}
}
</code>
</pre>
In practice, a new class of this dialect would look like:
<pre>
<code>
::tool::class create myclass {
# Use our new option keyword
option color {default: green}
}
myclass create myobj
puts [myobj cget color]
> green
</code>
</pre>
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