Hi everybody habe a strange problem in elm.
Just updated elm form 0.17 to 0.18.
Project was running fine in 0.17
Now the complier throws an error in 018.
That's what he's saying:
-- SYNTAX PROBLEM ---------- elm-stuff/packages/elm- lang/html/1.1.0/src/Html.elm
Ran into a single quote in a variable name. This was removed in 0.18!
9| , section, nav, article, aside, header, footer, address, main', body ^
Change it to a number or an underscore, like main_ or main1
Or better yet, choose a more descriptive name!
Anyone else has this problem?
What might be the problem: I use "main" already in
main : Program Never
Elm seems to have a problem because Html has the function main, too..
Might this be the case?
kind regards
Martin
Based on your error message, it looks like you are referencing an older version of the elm-lang/html package. You'll need to upgrade to the latest version.
The old source code had a function called main', which was causing the problem after the 0.18 upgrade. The single quote, or prime, was removed in Elm 0.18. Here's Evan's comment from the blog post about the 0.18 release:
Primes — Names like x' are no longer permitted. A younger me (one who was less concerned about nice variable names) certainly thought writing “x prime” was pretty neat! But in general, this syntax is too confusing to be worth it. Single quotes are generally associated with strings and characters. To see it unbalanced and part of a variable throws people off, and the benefit of having it is pretty small.
I've run into this problem. I've cloned the example project a long time ago and ran it then. I've ran the examples today after upgrading to Elm 0.18 and the problem occur. The solution was to delete the elm-stuff directory and restart elm-reactor which download the latest packages including html-2.0.0
Related
I'm looking for a way to "enter" a module in the REPL, so that I can access all symbols without qualification (not just the exported ones), and any function (re)defined at the REPL gets in the specified module. (Basically this is the functionality of Common Lisp's in-package macro.)
This would be useful in a REPL-oriented workflow, as I would be able to write the same code in the REPL as in the module I am developing.
The manual recommends a workflow where I qualify everything, but that seems annoying.
I started a package called REPLMods.jl for this a while back. It should probably be polished up, but I haven't had the time.
I spoke to core Julia members and there was interest in getting it merged into base once things were clean, but again, no time!
I know this isn't quite what you're asking, but just in case the 'obvious' had not occured to you (or future visitors to the question), assuming you loaded a module with an annoyingly cumbersome name, e.g.
import LaTeXStrings
and you don't want to have to type LaTeXStrings all the time just to explore its accessibles, i.e.
LaTeXStrings.[TAB]
you can just assign the imported module as a whole to another variable, i.e.
const l = LaTeXStrings
I'm sure in the absence of a more appropriate built-in solution, at least typing l.[TAB] as opposed to LaTeXStrings.[TAB]is a lot more tolerable :)
(I find it odd, in fact, that julia doesn't seem to support the import LaTeXStrings as l syntax ...)
It's 2020, I'm using Julia 1.4, and was unable to get REPLMods.jl to work. I think the following seem good enough for the time being:
ExportAll.jl - see Exporting all symbols in Julia for a discussion (just that one shouldn't ExportAll to replace normal export)
and Revise.jl
While trying to learn Frege I copied some code from Dierk's Real World Frege to the online REPL an tried to execute it (see also How to execute a compiled code snipped in Frege online repl). The scripts I've tried don't compile :-(
What am I doing wrong?
Here are examples of what does not compile:
println ( 2 *-3 ) -- unlike haskell, this will work!
and the whole ValuesAndVariables.fr code
It is unavoidable that over the course of more than a year, an evolving language (and its libraries) change so that older code will not compile anymore.
It would be nice, if we could see an example, instead of a generalization like "most".
The next best thing would be to have an issue in Dierks project that points to the error(s).
But the very best would be en effort to find out what is wrong. This would also intensify your learning process.
Here are two ressources that could help:
https://github.com/Frege/frege/wiki/New-or-Changed-Features -- the release notes for every release, contains a summary of things that have changed between releases, and especially the reasons why code would not compile anymore and how to correct it.
http://www.frege-lang.org/doc/fregedoc.html -- the library docs. May explain possible errors like import not found, or missing identifiers.
Go, give it a try. And I'm convinced Dierk will be happy to accept pull requests.
Edit: Fixes for announced errors.
The error in:
println ( 2 *-3 )
stems indeed from a syntactical change.
It is, as of recently, demanded that adjacent operators be separated by at least one space.
Hence
println (2 * -3)
However, the error message you got here was:
can't resolve `*-`, did you mean `-` perhaps?
which could have triggered the idea that it tries to interpret *- as a single operator.
The other error in ValuesAndVariables1.fr is indeed a show stopper for a beginner. The background is that we have one pi that has type Double and one that has type Float and potentially many more through type class Floating, so one needs to tell which one to print.
The following will work:
import Prelude.Math -- unless already imported
println Float.pi
println (pi :: Double)
the online REPL at http://try.frege-lang.org is currently based on Frege V3.23.370-g898bc8c . Dierk's code examples are based on V3.21.500-g88270a0 (which can be seen in the gradle build file).
It seems that the Frege developers decided to change the Frege syntax slightly between those versions. THe result is that you will not be able to run these code snippets in the online REPL anymore.
I have some code comments like this:
/**
How to use this method.
#discussion To use it, do something like the following
id hook = [[STDeallocHook alloc] initWithBlock:^{
// Do something when 'hook' is dealloced
}];
*/
So the code example is indented with 4 spaces. When I compile the docset with appledoc, it compiles correctly and shows the code as code in the API reference I generate. However back in XCode (Where I have appledoc creating warnings for issues in the doco) I get the warning:
Invalid [[STDeallocHook alloc] reference found hear STDeallocHook.h#16, unknown object: [STDeallocHook !
I think what's happening is that appledoc is looking for markdown links inside the code block.
How can I stop this warning from appearing?
I've been unable to stop it as well. It looks like it's been a known bug since 2011, but it's still broken.
Interestingly enough, I don't get it for everything. In a large code example, I'll only get a few of them... still haven't figured out how it determines to cause me grief or not...
Workarounds
This works around the warning, and looks fine in the generated documentation, but looks like crap in plain text: substitute the leading [ with the HTML escape code [
Future Fix
Supposedly, the mythical version 3 has addressed it, but I can't find any mention of an ETA for it. There is a "3.0exp1" branch from March 2012, and a "3.0dev" branch from October 2014.
If you have both the time and inclination, maybe you can see how it was fixed and patch it yourself (though the codebase has apparently changed a ton since then).
My Attempt
I felt unsatisfied with that answer, so, I went back and looked at the source code. First time in that code. It's not exactly easy to navigate... and none of the classes are documented, which I find quite strange, especially for a documentation tool.
Anyway, I think I know why I only get the warning sometimes. The parser treats all underscores as formatting markers. Thus, if it finds two of them in the same "block" of text, it splits them up. Since the code I tested on had category documentation, only the last one encountered in each "block" caused a warning... because all the others were treated as italics... and then ignored.
Also, it seems that I may be able to coerce it into skipping source-code blocks if they are marked as either...
#code
[self wjh_doSomething];
#endcode
or
```
[self wjh_doSomething];
```
or
~~~
[self wjh_doSomething];
~~~
The first is common in documentation blocks, the latter two in markdown.
It's a hack, but it seems to work. I sent a PR, which can be found here. Who knows if it will get accepted, but feel free to try it out yourself if you are so inclined.
I think I'll at least use it locally, as it cleans up a ton of warnings for me... and I may just go try to regenerate all my documented stuff to boot.
Edit
Well, I guess I should have gone and looked at the open PRs first. There seems to be a PR already sitting there that deals with the same issue, that has been there since May. It would have saved me time... but it was a little fun experimenting with it a bit ;-)
You may want to use that one... it seems to be simpler. Simpler is better, but I have not used that one and I'm not sure it completely ignores the blocks, but he seems to have quieted the warnings with his patch.
That one does not support #code/#endcode, which I'm glad to have.
I just finished skating around that infamous "cannot load main class start" thing, and I got blindsided with a sea of errors:
A friend suggests it might have something to do with com.google, but ultimately can't help me.
I haven't made a single alteration to any of the code so far. Eclipse just started up not being able to run and stayed that way. I think there's a way to fix it but it would require making acute changes at the sight of every single error; work that could be wiped by a cleanup if I'm proved wrong.
Anyone have a clue what the issue is? Thank you for the trouble.
UPDATE: Adding guava as a library relieved the error involving com.google, but threw in a handful of others. This one class file contains 3 of the most common unresolved types I've seen scattered throughout: Logger/LogManagaer, PropertyMap, and CrashReport
Your general problems revolve around not having dependencies in the build path. Eclipse's error messages are pretty clear about this; e.g. if a package name is underlined in red and can't be found, then that means it can't be found, and the obvious solution is to add the library that provides it, so that it can be found.
In virtually all cases here, a Google search for the missing packages and classes will lead you to the packages that contain it.
For each unresolved dependency, find the library, add it to the build path, then move on.
I also suggest consulting the documentation that comes with the source code you are attempting to compile, which often simply lists the dependencies, thus saving you the trouble of hunting them down as you go.
While we could do the internet searches for you and hash this out one step at a time, it's both better and faster for you to do it yourself. Better because if you're messing around with Minecraft source, having at least a basic knowledge of how your tools work is going to help you (I also suggest some of the material at http://docs.oracle.com/javase/tutorial/). Faster because the turnaround time of typing package names into the Google search box is a heck of a lot faster than constantly updating your question here and waiting for replies.
It looks like you are missing the Google Collections package, which now is called Guava.
Download the jar file, and add it as a library.
Is there a lint for Elixir (like for Javascript) which checks that every function has a type specification?
There is an Erlang compiler switch, +warn_missing_spec, which does this, but I'm having trouble getting it to work with Elixir at the moment, I think there is a bug with it's parsing of the ELIXIR_ERL_OPTS environment variable which is converting +warn_missing_spec into -warn_missing_spec which isn't a valid compiler option. I'm going to open an issue on the tracker, but thought you might like to know that this does indeed exist.
EDIT: As José mentioned below, the correct flag is ERL_COMPILER_OPTIONS. You can enable the missing spec warning during compilation by doing the following:
ERL_COMPILER_OPTIONS="warn_missing_spec" mix compile
Keep in mind you may get superfluous warnings from Elixir itself, for functions like __MODULE__. It should still be useful though. One last thing to note, I discovered this morning that there is a problem using this flag with mix compile, and that it's currently only warning about mix.exs. This is being fixed, and may even be fixed by the time you see this, but it's something to be aware of.