Comment by gnaritas | Hacker News Reader

Comment by gnaritas | Hacker News Reader

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I'm well aware, I've programmed in Pharo daily for a decade; I Smalltalk for a living.

What I said it true practically speaking, you're getting into implementation details that don't make a practical difference. Lisp and Smalltalk are both image based systems, but Smalltalk'ers actually work on the running live image all of the time, they aren't ever booting from the sources file nor are they ever editing it manually (excluding the one file based GNU Smalltalk), it's pared with a changes file to enable the IDE to expose the current source of a method but those are hidden implementation details whereas I'm talking about the abstraction presented to the programmer. Lispers "can" do this as well, and sometimes do, but Lisp has a much more standard general workflow of editing files that are then read and launched to create/patch a runtime image it's not the normal worflow to work entirely in the REPL which is essentially what Smalltalk'ers do.

Consider the difference, what Smalltalker's see in their code browsers is a text version of what's actually running; if they had macros, which are nothing more than code generators, they'd be seeing is the macro expansion rather than the original source call to the macro. Certainly Lispers "can" do this as well, they can macro expand something to see what's actually running but as their primary mode is editing the original source they're accustomed to seeing the macro unexpanded, they might define an accessor like

    (name :accessor person-name
         :initform 'bill
         :initarg :name)

And from experience know that an accessor is a getter, setter, and backing instance variable but they don't see those things in their editors, they just know they'll exist at runtime; whereas a Smalltalker is accustomed to looking at the runtime where he actually sees the getter, setter, and and backing instance variable.

Macros just don't fit into Smalltalk; they've been added before, people keep trying it, and it just doesn't fit and so doesn't catch on.

> editing it manually

You edit the source code via the IDE. Just like in Lisp systems. It's just that the IDE works differently.

> Smalltalk'ers actually work on the running live image all of the time

That's the dominant way to work in Lisp, too. My Lisp Machine even runs it as an OS. I use LispWorks for development on my Mac - the IDE is the running Lisp system.

> it's not the normal worflow to work entirely in the REPL

Actually that's the default mode. If you develop Lisp code with SLIME / GNU Emacs, it talks to a live Lisp system.

> if they had macros, which are nothing more than code generators, they'd be seeing is the macro expansion rather than the original source call to the macro.

That's not how Lisp works. Macros are not simple code generators, where the workflow would be write macro code, expand that, and use the expanded code. The Lisp developer is not generating code and working with that generated code. The generated code is usually hidden and generated by the Lisp system on demand/incrementally for internal use.

> And from experience know that an accessor is a getter, setter, and backing instance variable but they don't see those things in their editors, they just know they'll exist at runtime; whereas a Smalltalker is accustomed to looking at the runtime where he actually sees the getter, setter, and and backing instance variable.

In this case the Lisp developer sees the generated objects: the getter, setter slot definitions. What the Lisp developer usually does not look at is the code generated by the macros. It might be useful to have source code for the macro forms and being able to edit them, but it is usually not done in Lisp. There are many macros, where there are no generated objects and the resulting code is extremely complex and large. Thus it would not make sense at all to present this code or edit this code...

> don't see those things in their editors, they just know they'll exist at runtime

I'll see it in the runtime. The introspective capability tells me that it is there. If I want to edit them, I would then go back to the source. For example when I call (ed 'foobar) to edit the accessor foobar, it would open up the defclass form in the editor. Some Lisp systems (like LispWorks)also offer the link back from the objects to the macro form which was responsible for creating them. What I usually don't want to see is the generated code, since that's not fit for human consumption.

> Macros just don't fit into Smalltalk; they've been added before, people keep trying it, and it just doesn't fit and so doesn't catch on.

Because they difficult to integrate into Smalltalk and its idea of an IDE. Macros add a lot complexity to the system and how the developers are using it. They offer code manipulation and the price is losing a direct connection of the object code / the objects from the source code.

> That's not how Lisp works. Macros are not simple code generators, where the workflow would be write macro code, expand that, and use the expanded code.

You're putting words in my mouth, and yes macros are just code generators. I didn't imply or say they're expanded and then devs use the expanded code. The whole point of them is you're not supposed to think about or see the generated code, the macro becomes the abstraction the dev works with.

> In this case the Lisp developer sees the generated objects: the getter, setter slot definitions. What the Lisp developer usually does not look at is the code generated by the macros. There are many macros, where there are no generated objects and the resulting code is extremely complex and large. Thus it would not make sense at all to present this code or edit this code...

Exactly the point I was making. You're actually agreeing with me though the tone doesn't come off that way.

> Actually that's the default mode. If you develop Lisp code with SLIME / GNU Emacs, it talks to a live Lisp system.

I said multiple times Lisp "can" work that way, stop being so defensive. But the point in fact is most Lisp developers don't work that they, they don't live in the REPL full time like Smalltalk devs do, you load from source quite often in comparison to the 0 times Smalltalk'ers do.

Look this isn't a competition; Lisp is technically superior to Smalltalk in features both due to macros and due to CLOS and its multiple dispatch OO system. Lisp was the inspiration for Smalltalk, Alan Kay goes so far as to call eval/apply the Maxwell's equations of computer science. However, I any many others having tried both Lisp and Smalltalk, prefer Smalltalk largely due to the syntax and dev environment. Emacs and Slime just don't cut it for us. Generic functions don't feel like object orientation, the way Smalltalk does OO just feels better and the dev environment feels better than anything else out there.

> I said multiple times Lisp "can" work that way, stop being so defensive. But the point in fact is most Lisp developers don't work that they, they don't live in the REPL full time like Smalltalk devs do, you load from source quite often in comparison to the 0 times Smalltalk'ers do.

That Lisp developers load source does not mean that the image gets restarted. Lisp usually is designed such that you can incrementally update/manipulate the running image. As I said that's the dominant development style for Lisp, AFAIK.

> the dev environment feels better than anything else out there.

That's what my friends who still use Symbolics Open Genera tell me all the time. ;-)

On living in the REPL full time and having a better environment, is there something you wish Smalltalk could do to become a better environment that it doesn't?

What would feel better?

Yes, several, it's slightly too dependent on the mouse for focus; I'd rather never touch a mouse. I wish it used native windows (this is specific to Squeak/Pharo) so my editor felt like any other editor rather than a window within a window that it currently is (some other Smalltalk's do this but they're windows based and I'm on Linux). I wish the code browser had a back button so I could go dig into the source of something and then come back rather than popping a new browser to investigate that thing. Even better I'd like bookmarks like you get from more modern IDE's where you can mark a few key spots you want to constantly be jumping between rather than having a different browser open on each one.

> Actually that's the default mode. If you develop Lisp code with SLIME / GNU Emacs, it talks to a live Lisp system.

So do you dump your image at the end? My understanding is that most people work with files, and execute stuff occasionally while they're editing, then save the files. Next time, you reload from source - you don't start from an image with state. And if you fail to run something, your source and your repl become out of sync.

I've never seen anyone actually doing image-based development in a lisp, despite some lisps supporting it - even in livecoding (music), the standard is to edit a file, then occasionally send parts of the file to a repl.

> So do you dump your image at the end?

For example if you deliver an application, that's what one usually does.

> My understanding is that most people work with files, and execute stuff occasionally while they're editing, then save the files

One works with files, but together with the running Lisp system. I would work with a mix of compiled (fast load) and source files. Let's say you work on a new version of your graphics editor. You start the Lisp image and load the current version into it - mostly from fasl files. Some years ago people would more often have started a dumped image, because it took some time to load the fasl files. Even today, if the program is really large, you might want to use a dumped image of some version of it.

But independent of how you reach there, you start Lisp and then recreate a state of the working image (either from a dumped image or from loading files), where you continue to work from.

The image then will have a the development information, debug information, application state, compiler info, ...

In Smalltalk you would typically load a saved image more often. In Lisp you would recreate the state from a base image and then fast-load the stuff you need.

> And if you fail to run something, your source and your repl become out of sync.

Yes that happens and current Lisp systems actually don't have a goal to keep that in sync. You have to check manually that the source or the compiled system actually loads and runs - means recreate the correct state.

> I've never seen anyone actually doing image-based development in a lisp, despite some lisps supporting it - even in livecoding (music), the standard is to edit a file, then occasionally send parts of the file to a repl.

In the sense of Smalltalk (image + managed source code) there are only few people doing that in Lisp - nowadays. That debate (managed code images vs. a mixed file/image model) was lost in the early 80s with some later attempts to create a manage source model with code in data bases.

In the sense of saving images as pre-loaded code, that's seen and especially for application delivery. The LispWorks IDE I'm using has a lot of stuff pre-loaded (with some on-demand loading) as a single image. If I develop something, it is loaded into it and the application then is a newly dumped image. LispWorks also supports some exotic stuff like regularly saved sessions. It also keeps track which sessions have been saved based on which other sessions.

http://www.lispworks.com/documentation/lw70/IDE-M/html/ide-m...

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