[Seaside] still struggling with the confusing scripting API's

[Johan Brichau]

Hi Chris,

It is *possible*:

	html script with: ((html javascript alias: 'MyJavascriptObject') apply: { (html javascript alias: 'document') call: 'getElementById' with: #id1 }) create

One important thing to know is that the Seaside script generation api does not cover all possible Javascript expressions.
I believe it was never intended to cover the complete language either. We can, of course, always extend the possibilities.

Our experience is that it does the job to glue Seaside-JQuery generated expressions to hand-written Javascript, or for small pieces of JS code.
If it’s harder to write the JS code in Seaside, then you should not try to write it in Seaside ;) I mean: it’s not as succinct as the concrete syntax because we’re generating something like Javascript ASTs here.
I would definitely opt for this version:

	html script with: (JSStream on: 'new MyJavascriptObject(document.getElementById(''#id1''))’)

Alternatively, the following is possible by adding a simple convenience method:

	html script with: ((html javascript create: (html javascript alias: 'MyJavascriptObject') withArguments: { (html javascript alias: 'document') call: 'getElementById' with: #id1 }))

With JSObject>>create:withArguments: implemented as:

create: anObject withArguments: aCollection
	"new <anObject>(<aCollection>)"
	^ (anObject apply: aCollection) create

Depending on your use case, the other options are:
- use handwritten javascript functions and call those from generated scripts, limiting the constructs you need to be generated to those that can be done well in Seaside
- generate javascript strings instead of ASTs, as in my final code snippet.
- write a complete wrapper library like how it’s done for jQuery to work with your Javascript library.

Hope this helps
Johan

> On 30 Oct 2015, at 17:52, Chris Muller <ma.chris.m at gmail.com> wrote:
> 
> I'm still trying to get my head around "what is the best way to write
> javascript in Seaside.  I just spent an entire morning and still
> failed to write the simplest expression via an aggregation of
> Seaside's JSDecoration's.  This is what I want to render:
> 
>       new MyJavascriptObject(document.getElementById("id1"))
> 
> Using Seasides various brushes and canvas API, I could not even get
> the first two words right.  I tried:
> 
>        html script with: (html javascript create access: 'MyJavascriptObject'))
>        html script with: (html javascript create add: 'MyJavascriptObject'))
>        html script with: (html javascript create alias: 'MyJavascriptObject'))
>        html script with: (html javascript create assign: 'MyJavascriptObject'))
> 
> None of those produce "new MyJavascriptObject", what am I missing?
> Its almost like there is a missing JSDecoration or capability missing
> from JSStatement..?
> 
> After throwing up my hands with that, I decided to try "hard coding"
> the Javascript strings into my Seaside rendering methods:
> 
>      html script with: (html javascript script: [ : s | s add: 'new
> MyJavascriptObject(document.getElementById("', (aPufDomainComponent
> htmlId),'") ])
> 
> which produces:
> 
>     new MyJavascriptObject(document.getElementById(\"id1\")
> 
> So that is pretty much what I want, but see that it is escaping the
> quote characters, which makes it hard to read in the browser.  Are
> those necessary or is there some way to avoid that?
> 
> I wanted to avoid having to put big chunks of hardcoded Javascript
> strings into my Smalltalk code.  Any advice is appreciated.
> 
> - Chris
> 
> PS -- I think the inconsistency of the API is part of my struggle.
> JSObject script: can accept a Block, and WAHtmlCanvas>>#script: SAYS
> it takes "aBlock", but that HAS to be wrong, because
> WAScriptTag>>#with: ends up writing the Block's "greaseString" to the
> stream...
> 
> thanks.
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