Less #import not working as expected - less

I have an issue where I can't quite understand why the Less #import option is not working as expected despite trying numerous Less #import options. Here is the file in question (app.less):
#import "theme";
.nav-wrapper--background-white {
background-color: #ffffff;
}
Initially, when I enter valid Less code in theme.less, the Less compiler does a few things:
1) It generates theme.css.
2) It generates app.less that includes the CSS from theme.css.
This is great. However, if I make subsequent changes in theme.less, the Less compiler regenerates theme.css with the revised changes but, the changes in theme.css are not merged into app.css.
What I am hoping will happen is that whenever I make a change in the referenced theme.less, its theme.css will be included in app.css.
I do this sort of thing in SASS/SCSS and it works as expected. I only started with Less yesterday and assume that the same thing can be achieved. Any pointers would be greatly appreciated.

This sounds like a problem with your compiler. I'm assuming from your tags that you're using, as what you're describing sounds like expected behavior.
How are you compiling your less?

Related

Getting reference error from appledoc when embedding code in comments

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.

Getting rid of redundant #import lines

In my Cocoa development, every so often I include a header into a source file so I can use a particular class in it. But then later I delete that code from the source file, and forget (or don't really want to worry about) deleting the corresponding #import.
With time, a lot of redundant #import lines pile up in my source files, throughout the codebase.
Now, I know that these lines cause no harm, but is there any easy way to get rid of them automatically? At least it would make the top of every file cleaner ;)
There's a tool that does this for C and C++, but as far as I could tell, it doesn't yet support Objective-C. I've filed a ticket to ask for that.
nothing comprehensive off the shelf comes to mind.
1) JetBrains' AppCode may help. It's quite young at this time (e.g. not even 'beta', but it is publicly distributed), and doesn't fully understand structures of includes and nontrivial xcode projects and build settings, but it is likely smart enough to handle simpler cases.
2) you could create some scripts to accomplish what you're after. it wouldn't be terrible if you already have a project which builds out everything using common build settings. doing this manually is a pain, and is usually not a good use of time in larger projects if you are not using a high level of automation.

Rename ptrace funct something else? How?

In code, I'd use
#include <sys/types.h>
#include <sys/ptrace.h>
ptrace(PT_DENY_ATTACH, 0, 0, 0);
to deny attaching to the process. I was wondering if there was a way to rename "ptrace()" to something less obvious. I tried copying ptrace.h into my own header file and changing int ptrace to something else, but that just failed with an undefined symbol error. And I can't find any other references to the function :\
Thank you in advance for anything on this.
ptrace is a system call. Even if you renamed that function in your C code, the actual ptrace call would still have to be made, so it would be visible in for example strace output (with all the parameters).
Using a macro trick will only make it very slightly less obvious (you'd need two greps instead of one to find it in your codebase). So I don't really see the point. (A macro trick would not change anything to the compiled code.)
You could try running the actual syscall yourself with syscall, but that's a lot of work and still wouldn't hide anything to strace up to that point. It would make it just a tiny bit harder to break there in gdb.
So IMO: what you're trying to do is not worth the effort.
Use #define in your header to create a new macro:
#define MyTrace(a,b,c,d) ptrace(a,b,c,d)

code running very slowly after importing ansi c into iphone project

I have an ANSI C code that is about 10,000 lines long that I am trying to use in an iPhone project. When I compile the code with gcc on the command line, I type the following:
gcc -o myprog -O3 myprog.c
This program reads in large jpeg files and does some fancy processing on them, so I call it with the following
./myprog mypic.jpg
and from the command line, this takes take about 0.1 seconds.
I'm trying to import this code into an iPhone project but I'm not entirely sure how. I was able to get it to compile and run successfully by renaming myprog.c to myprog.h and then calling the functions in the C code from within a generic NSObject class. I added the O3 optimization to the project's Other C Flags. However, when I do this, the code on the simulator takes about 2 seconds to run and on the iPhone about 7 seconds to run which renders an unacceptable user experience.
Any tips on on hoe to get this going would be much appreciated.
It's hard to say for sure where the slowness comes from, or if there is any way around it, but right off the bat you've done something wrong.
You shouldn't have renamed a .c file to a .h file and included it. You should have written a .h (header) file that had the function, variable, and type declarations declared:
myprog.h:
#ifndef MYPROG_H_
#define MYPROG_H_
struct thing {
int a;
int b;
};
extern int woof;
int foo(void * buf, int size);
#endif /* MYPROG_H_ */
Then you should compile the .c file to an object file (or library) and link the main program against that. If you were to have included the .h file that was really just a renamed .c file into more than one source code files it may have resulted in having multiple versions of some data and code in your program.
You'll probably also want to go through and separate out any code in myprog.c that you won't be using in your iPhone program. I'll bet that there is plenty.
As far as why the program is slowing down, this could have to do with myprog being written to make use of some resources that aren't available on the iPhone. The first thing that comes to mind is large amounts of RAM, since many desktop applications are written as though available RAM is infinite, and I could see how some .jpg manipulation code could be written this way. The way to get around this would be to try to rework the algorithm so that it did not load as much of the picture at one time while working on it.
The second thing that come is floating point code. Floating point operations are common in image manipulation code, but often either not available or severely limited in embedded systems. In the case of iPhones they are available, but according to something I heard, their performance is noticeably hampered if you compile your code to thumb rather than regular ARM code. (I've never developed for an iPhone or its particular processor so I don't know for sure, but it is worth looking into).
Another place where things could be slowing down would be if there were some sort of translation between Objective C objects and C structures that you have somehow introduced and is happening a lot more often than it should need to. There are probably other slow downs that could happen because of this, but you might be able to test this theory out by creating a objective C program for your desktop that uses the myprog.c code in a manner similar to the iPhone program's use of it.
Another thing you probably should look into is profiling your iPhone program. Profiling determines (or only helps to determine, in some cases) where the program is spending its time. Knowing this doesn't necessarily tell you that the code that runs the most is bad or that anything about it could be improved, but it does tell you where to look. And sometimes you may look at the results and immediately know that some function that you thought was only going to be called once at the beginning of the program is actually being called repeatedly, which highly suggests that some improvement can be made.
I'm sure that a little searching will turn up how to go about this.

Can Make undefine a variable?

I'm working in an embedded system (RTXC) where I need to disable the debugger functionality which is enabled through a #define command. However, when I change the #define to undefine, compilation goes off fine, but when the linker runs, it encounters an error about a symbol not existing that belongs to the debug code (which should have been taken care of by the debugger variable not being defined). Is there any way for Make to ensure that a preprocessor variable does not get defined or stays undefined ?
The answer to your question is no, Make can't absolutely prevent a variable from being defined by, say, a #define expression in the code.
You seem to have an elusive problem. It could be a bug in your Makefiles, a misspelled directive, a bad macro (if you'll pardon the tautology) or something trivial. I'd suggest burning the forest: cut out everything until the problem stops, then see where it was hiding. If you get down to HelloWorld and the problem persists, let us know.
No. You will need to fix the bug in your code.
More specifically, there is something that is referencing the debug side of things outside of an #ifdef. Make won't be able to help you there.
Another possibility is that you have a .o or something left over from a previous build; you might want to try cleaning the build tree.