* Tests are now common and considered a good thing. A new contributor can write code without worrying about breaking rarely-used functionality.
* Many languages have package managers. Using latest third-party library is now simple
* We have great deployment mechanisms -- one-command deployments are common, containers and version pinning help reproducibility.
* Some languages come with support for interactive REPL -- you can evaluate arbitrary commands inside running processes.
* Many languages support static checking -- a lot of errors could be caught even if the code is never exercised
* Many languages need no compilation at all -- just edit the file and run it
What can smalltalk offer? Obviously it has great REPL. Anything else? What is the cool new 'software development process' feature that you are referring to?
For example, I have found exactly one sentence about version control and sharing in the article you have linked: "We may even see Pharo 7, which promises a Git-integration tool called Iceberg for source code version control." . Is this what you wanted to show me? Because my takeaway is that the only way to work on Smalltalk software as a team is to use file-based tools (git). I see no improvements in software development process here.
The other commenter mentioned Monticello and Smalltalk Hub. Ok, this looks like a decent version control system. It is interesting how without files, you have to add a prefix to a name of every class and tag each function which you want checked in. Still, I could not find which features it has that git does not.
- Software development using files and folders is absolutely antediluvian. Smalltalk does everything in a universe of objects; source code is organized spatially rather than in long reams residing in text files.
- Live coding and debugging done right is an enormous and unparalleled productivity booster.
- Persisting execution state is extremely convenient for maintaining continuity, and hence the high velocity of development.
Governments and enterprises have long used Smalltalk to write massive applications in large team environments using Smalltalk's own tooling for collaboration and version control. There's no question that historically Smalltalk has not played well with the outside (file-based) world, and this has been a major point of contention.
If you insist on using Git and similar tools with Smalltalk, then yes, this is problematic. The point is, if you view software development from only one perspective, you deny any possibility of improving the process in other ways that can lead to dramatically improved productivity, accelerated development, and lowered cognitive stress.
Specifically, let's imagine this scenario: we have team of tens of programmers working on a project. A new team member joins and accidentally breaks the code in non-obvious way. He pushes the code to main repository. Next time, everyone else checks out the latest version of the code and starts having weird problems. If you had 20 people on team, and they each wasted 2 hours because the code was broken, well, you just wasted a week of programmer time. How do you prevent it?
In file-based word, the answer is tests and CI. What is the smalltalk way? And please do not say "It's in the conceptual nature of programming" -- if the scenario makes no sense in the smalltalk world (maybe you are not supposed to have 20 people working on the same project?) please say this.
Pharo works well also with usual VCS because it can export code into source code files.
The image plays no role in VCS whatsoever because VCS is about code, not data, and image is mostly about live data and less about live code.
So any tool will and does work with Pharo outside the image. Problem arises with a majority of people that prefer to stay in the image; in that case you gain more control because you have more Pharo code to play with, but you lose a lot of power because we are a small community not able to compete with behemoth projects like git.
Another interesting thing which Pharo does emphasize is remote debugging: though not a Pharo monopoly by a long shot, we do have several libraries that can achieve this, and because the image format retains live state and live code execution, it's easy to resolve issues.
Besides the image format, the Fuel format has the advantage of storing only a fraction of the image. You can email this or share it via git or Dropbox. Like an image, a Fuel file is a binary file and, like the image, it can store live state and live code execution. This way, you can isolate live bugs and share them with your team, each one in its own Fuel file.
STON is also another alternative format which feels familiar for those that have worked with JSON.
So you see, you get the best of both worlds. You have the fantastic Smalltalk image, and you have ways to deal with the file-based world.
1. Breaking code is nothing specific to a language. The usual weapon also in Smalltalk is to monitor if something breaks - for instance by using CI. Continuous integration only makes real sense when you have tests.
One should remember that "test first", "unit testing" and "Extreme programming" (XP)
like many other things had their roots in Smalltalk. Because in dynamic
languages testing using code was and is part of the culture (ranging from lively verifying
with workspace expressions and inspectors up to fully written tests).
The first unit testing framework "SUnit" was written by Kent Beck for
Smalltalk (SUnit), later he ported it to Java with Erich Gamma on a flight
to OOPSLA OO conference. Java helped to push the popularity afterwards.
Meanwhile also static language enthusiasts have understood that it is better to
rely on tests than type checking compilers and they now hurry up to follow
what Smalltalk already had years ago.
One last thing you should try: try to query your system how many test methods were
written. When you solved this easily with a Smalltalk expression retry
this in Java ;)
2. Commercial Smalltalks which are often used in big projects provide solutions
which are repository based like the famous ENVY (written by OTI, was
in VisualAge for Smalltalk from IBM, now VAST) or Store (VisualWorks). For
more details try the commercial evaluation versions or read [1] or [2].
A screenshot of Envy can be seen in [3]. I worked with ENVY and it is really
good - but mostly only for internal work/teams. If I remember correctly
ENVY once was also available for VisualWorks (VW) ... but later got replaced
for business or license reasons. I'm not sure about that point.
Cincom developed Store for VW as a replacement which is also nice as it allows to work
in an occasionally-connected mode, so work offline and push packages/versions later to
a central team repo.
In the open source world there are different solutions (including Monticello
which is available for nearly all Smalltalk derivates) or newer solutions
like FileTree or Iceberg allowing to work with Git.
The workflow depends on the tool and your requirements.
3. Often it makes sense to automatically build and regular distribute a fresh daily
developer images to the members of your team. This helps in later merging
code.
For instance Kapital (a big financial project from JP Morgan) works that
way and I've seen that model very often. See [4]
Again nothing special to Smalltalk. In more file based languages it also makes
sense to stay close to the main line and merge as well as resynchronize with the
team.
In Pharo for instance we have the PharoLauncher that allows you to download
any (fresh or old) image built provided by the open source community.
3. Versioning can be done on many levels. Simplest level is the image itself.
Smalltalk not only has an VM and image concept - but also the concept of a changes
file. If you evaluate a code expression, create or modify a class or method
in the system this gets logged there.
It prevents you from loosing code and it is easy to restore quickly for instance
an earlier method versions/editions that one has implemented.
Most Smalltalks now also work with packages and you can define package
dependencies as well as declaring versions that fit together to provide
a project, goodie or app (for instance with a Configuration class in Monticello)
While in file based languages this is often done in an XML file (Maven for instance)
or a JSON file in Smalltalk this is usually expressed with objects and classes again.
This also makes it more flexible as you can very easily do queries on it or
use refactoring tools to even restructure or reconfigure.
4. Usage of shared code repositories is very common also in Smalltalk. While you
now can also use GitHub, GitLab, Gogs and others with Iceberg and friends in Smalltalk
there are also repository systems implemented in Smalltalk itself like
- SqueakSource (http://source.squeak.org, http://squeaksource.com)
- SqueakSource3 (http://ss3.gemtalksystems.com)
- SmalltalkHub (http://smalltalkhub.com)
5. Beside repositories where code and goodies are hosted one often finds registries
with infos about loadable components.
Pharo for instance has http://catalog.pharo.org which is accessible also
directly from the image.
5. If you work in a team you can also use a custom update stream. This is how
for instance open source projects like Pharo and Squeak are managed.
So anyone can hit an "update" button to get the latest changes.
In Pharo http://updates.pharo.org is used and you can have a look at UpdateStreamer
class to see how easy that works over the web or how to customize it for own needs.
7. If one requires not only collaboration for the development team (coding) but
would like to collaborate also with other projects members on other artefacts
(Excel, project plans, documents, ...) then one should have a look at tools like this
http://www.3dicc.com
which is implemented in - guess what: SMALLTALK.
[1] https://www.cambridge.org/core/books/mastering-envydeveloper... [2] http://www.cincomsmalltalk.com/main/documentation/VisualWork... [3] http://www.edm2.com/index.php/Installing_the_VisualAge_UML_D... [4] http://www.slideshare.net/esug/13-yanndmonclair
For testing it doesn't matter where the tests come from. Certainly some test environments look for tests in files with predetermined names, or in particular directories, but that's an implementation detail. Look at Rust for a modern compiled file-based language that completely avoids that; instead you tag individual functions with metadata to indicate that they are tests. At build time you can create both a normal binary and a test binary; the first is the program you wrote, the second runs the tests that you wrote.
REPLs and a mixed compiler/interpreter were both invented by Lisp, which is largely image-based. They go hand-in-hand; code you enter at the REPL might start out interpreted, but you can always call the compiler (at run time) to speed up functions you care about (or let the system do it automatically).
The static vs dynamic language divide has nothing to do with how the code is stored, but historically languages with REPLs have indeed been dynamic languages.
I don't know about Smalltalk specifically, but Common Lisp has a great package system, and with Quicklisp it's a fully modern one with automatic package installation, dependency management, version pinning, and everything. Of course, Common Lisp these days is a hybrid system. Your code is stored in files, and when you load them into memory to create an image. If you care about startup time you can dump that image out so that it loads all at once. Quicklisp just has to download a tarball of files and stick them in your load path for you; I don't know precisely this is done in Smalltalk.
Both Lisp and Smalltalk have a facility for writing code out to a file to be printed, sent across the network, etc. This is how collaboration is done. You write the code in your environment, test it, etc. Then you write it out to a file and send it to whoever. (Or your version control system puts it in a file for you when you commit, etc.)
I think both you and I agree that software development process improves mostly independently from file-based/image distinction. There are no visible ways when files are "holding back" the software development.
A peculiar perspective of Smalltalk programmers is to consider that "code in files is dead code". External tools are needed to query it, modify it, compile it.
In Pharo you can evaluate... Integer methods first inspect
and in different tabs you can see this method's source code, the AST, the compiled bytecode.
Or in a similar way we can look at how PLUS is implemented by evaluating (Integer>>#+) inspect
Or look at all the methods that use PLUS
#+ senders inspect
btw, xUnit testing originated with Smalltalk. https://en.wikipedia.org/wiki/SUnit
> * Many languages have package managers. Using latest third-party library is now simple
Metacello is Pharo's tool for defining dependencies between libraries [1][2]. [1] http://sleepycoders.blogspot.com.au/2013/10/dead-simple-intr... [2] http://pharobooks.gforge.inria.fr/PharoByExampleTwo-Eng/late...
> * We have great deployment mechanisms -- one-command deployments are common, containers and version pinning help reproducibility.
Pharo Catalog provides a GUI one click installer of Metacello configurations https://pbs.twimg.com/media/CHajfSAWUAEpCBM.png
You can also load Metacello configurations from the command line per last snippet of [1]
Metacello provides version pinning.
You might consider every Smalltalk Image to be a container. Its like a uni sports tour. What happens in the Image, stays in the Image ;)
> * Some languages come with support for interactive REPL -- you can evaluate arbitrary commands inside running processes.
As you say, Smalltalk has a super REPL. How easy is it for other REPLs to modify and query the code of the system? For example in Pharo if I define a class and methods like this...
Object subclass: #MyClass
instanceVariableNames: 'count'
classVariableNames: ''
package: 'Demo'.
MyClass compile: 'setCount: anInteger
count := anInteger'.
MyClass compile: 'getPlusFive
^count + 5'.
MyClass methods asString > What can smalltalk offer? Obviously it has great REPL. Anything else? > What is the cool new 'software development process' feature that you are referring to?
For me, the greatest thing about Smalltalk is the very tight code/compile/debug loop. Indeed, its common to "code from within the debugger" where you compile your first method calling methods that don't exist yet, and when execution hits them, the system asks you to define that method and then continues execution. This is great for protoyping and (purely subjective) I feel program architecture ends up being closer to how a "user" of the library would like it layered.
A video by someone outside the Pharo community (Avdi has published several books on Ruby) shows a bit of this [3] https://www.youtube.com/watch?v=HOuZyOKa91o&t
Now this is not "cool and new" for Smalltalk. It has had this since 1980. But its a "blub" [4] feature that not many people get exposed to. The saying goes "the only languages worth learning are those that change how you think about programming". And for me, this is what changed how I thought about programming. [4] http://paulgraham.com/avg.html
> For example, I have found exactly one sentence about version control and sharing in the article you have linked: "We may even see Pharo 7, which promises a Git-integration tool called Iceberg for source code version control." . Is this what you wanted to show me? Because my takeaway is that the only way to work on Smalltalk software as a team is to use file-based tools (git). I see no improvements in software development process here.
Git interaction is not what Pharo is selling a better development process. But its an important thing for the Pharo community to make it easier to participate in polygot projects. Historically one of the common criticisms that Smalltalk was insular and didn't play well with others. Monticello had three-way merge for a long time so we were able to live a long time without external version control. Monticello works well for small teams, but doesn't scale well to Internet size teams. We've now recognized those other advances and fixing those reasons "not to use Pharo."
The advantage of Pharo is not so much inter-developer processes. Its simliar to other languages, especially now we are integrating. Pharo's benefit is improving the "flow" of moving thoughts into code. The very tight code/compile/debug loop and minimal syntax reduces the friction of coding.
I heard of a few projects where clients initially resistant to the use of "new" technology like Pharo, but accepted using Pharo to prototype with - but in the end were very happy to leave it all in Pharo.
> The other commenter mentioned Monticello and Smalltalk Hub. Ok, this looks like a decent version control system. > It is interesting how without files, you have to add a prefix to a name of every class and tag each function which you want checked in. Still, I could not find which features it has that git does not.
This prefixing of class names has nothing to do with sans-files. It is just that Pharo does not have namespaces. This does leave the potential for name classes, but in practice the prefixing works well. btw, as another minor demonstration of Pharo REPL, you can change every reference to the class in one line like this...
MyClass rename: 'OtherClass'.
obj := OtherClass new.
obj setCount: 5.
obj getPlusFive inspect.So doesn't that imply that Smalltalk was wrong to think we wouldn't be using file-based tools in 50 years..?