Pharo Curl

It took some effort again to get Curl markup running as an alternative to HTML+JavaScript on Seaside 3.0 on Pharo 1.1.1 Smalltalk.

The worst nuisance was Seaside using a method named text: for the equivalent of stream nextPutAll: or document print

This is because text is a common declarative identifier in Curl markup.  But it is only an annoyance and without examing available selectors at runtime or usinf perform: I can't see a workaround while leaving Seaside intact.

What was vexing was to still have to modifiy the WAAdmin class to defeat HTML-bias built into the framework.  And one or two other known quirks.

If only Seaside would embrace Traits on Pharo Smalltalk!  Traits would make it so clear that the choice of markup can be separated from the choice to use continuations, to use halos ...

Traits might also reduce the reliance on the Decorator pattern.  In a language with late binding, this leads to odd code, such as assigning a stream to an object whose class name and instance identifier clearly mean that it is not a stream ( but of course it is a decorator of a stream.)

Traits might reduce the reliance on the visitor pattern whcih I think reduces the understandability of code far more than double-dispatch itself because of the proliferation of visitor classes.  It is no longer necessary to ake a virtue of that necessity ( dare we now say, 'limitation' ?)

Many things are improved in Seaside 3.0 so that overall flipping from HTML markup to Curl goes well in the details - especially in a reduced need to subclass where closed tags happen to be identical across HTML and Curl.

It was amusing to me this time to add crlf so as to get better formatted Curl markup to inspect using the Curl source inspector - and spc to put spaces into the markup layout itself (Curl ignores whitespace the same an HTML client.)

The one concession was to use txt: to dump plain text - but super was not enough to preserve a Curl text: tag - for that I had to look at the runtime class so blocks go to text: and strings go to the canvas encoder for printing.

Curl 'attributes' (properties and options) are laid out the same as Seaside HtmlAttributes so anyone who can layout HTML for Seaside can layout Curl while remaining on 'the gentle slope' of the Curl language when used for declarative web content markup.

It still may be that Aida will be a better home for Curl poetry markup on a Pharo Smalltalk web server.