Scumbag Steve and Y U NO guy
Scumbag Steve broke the build
IntelliJ Idea Y U NO STOP STEALING FOCUS?
Popularity: 6% [?]
Mono on Ubuntu: Package dotnet35 was not found in the pkg-config search path
I’m taking a C# and .NET class at ASU East. Our professor has example code that runs on Windows and the Mac (using Mono). I installed mono 2.8 from this link and I was able to get C# code to compile. However, when I tried to run my professor’s build script (he uses ant with some .NET extensions), I got the following error:
[dn:csc] Package dotnet35 was not found in the pkg-config search path.
[dn:csc] Perhaps you should add the directory containing `dotnet35.pc’
[dn:csc] to the PKG_CONFIG_PATH environment variable
[dn:csc] No package ‘dotnet35′ found
[dn:csc] error CS8027: Error running pkg-config. Check the above output.
To fix this, I set the value of PKG_CONFIG_PATH to /usr/local/mono/2.8/lib/pkgconfig (you’ll need to add this to your .bashrc). If you used the mono install-script without modification, then the value of PKG_CONFIG_PATH should be /opt/mono-2.8/lib.
Popularity: 3% [?]
Bytecode optimization in Java
I learnt something new about bytecode optimization today. In languages like C and C++, if you’re really concerned about efficiency, you can drop into assembly mode and write specific assembly code instead of relying on the compiler to convert your C/C++ code into assembly (compilers can optimize, but not as well as humans in all cases).
I saw a question on Stackoverflow today that talked about the getfield opcode in the context of the trim() method in the String class. In the trim() method, you have the following comments:
int off = offset; /* avoid getfield opcode */ char[] val = value; /* avoid getfield opcode */
The author of the question wanted to know what these comments mean. This question seemed pretty interesting to me and so I went and did some research. I found out that getfield is an operation that lets you get access to the member variable/field of a class. This operation is fairly expensive as it involves indexing into the runtime constant pool. Performing this operation a few times does not really incur a performance hit. It is when you perform the operation multiple times, that performance becomes an issue. You can see this from the next few lines of code:
while ((st < len) && (val[off + st] <= ' ')) {
st++;
}
while ((st < len) && (val[off + len - 1] <= ' ')) {
len--;
}
Now if the author of the trim() method hadn’t assigned offset and value to local variables, a getfield operation would be performed every time the loop-condition is tested. This is obviously inefficient. Therefore, the author assigned the the values of offset and val into the local variables off and val. So now, instead of getfield you have iload (for off anyway), which performs much faster.
Popularity: 4% [?]
Anonymous self-invoked recursive-function in Javascript
I needed to do an n-ary tree traversal recently with some Javascript code that I’m working on and I initially wrote an iterative n-ary tree-traversal algorithm (using a node stack with a while loop). I wanted to keep track of some extra (depth-dependent) data during the traversal and I didn’t like the way I was forced to do it with the iterative algorithm. I also didn’t feel like adding a new function to the namespace. Then I realized that you can create function-literals in Javascript and self-invoke them. So I ended up with the an anonymous self-invoked recursive function. Here’s the basic skeleton for an n-ary tree traversal (this one is pre-order):
(function(node){
for(var i = 0; i < node.children.length; i++) {
console.log(node.data);
arguments.callee(node.children[i]);
}
}(root));
You can also do a binary tree traversal (this one is also pre-order):
(function(node){
if(node != null) {
console.log(node.data);
arguments.callee(node.left);
arguments.callee(node.right);
}
}(root));
Seems very elegant and also very Lisp-like to me (must be the parentheses!)
Popularity: unranked [?]
StackOverflow FAIL
I saw this question on StackOverflow today. I thought it was hilarious!
Funny StackOverflow question
Popularity: unranked [?]
Regula: An annotation-based form-validator written in Javascript
Regula is an annotation-based form-validation framework written in Javascript. There already exist a few frameworks that address form-validation in Javascript, but I have found them to be somewhat lacking. I have thought about writing one of my own for some time, but I honestly had no idea what form it would or should take. I knew that I wanted to make one that was easy to use, flexible, and easily extensible (custom validation rules). I finally got an idea as to the form my framework should take, when I was looking at Hibernate bean-validation. I like the fact that you can set constraints by using annotations like @NotNull or @NotEmpty. That way, when you look at the bean, you are immediately aware of the constraints attached to it. I wanted to do something similar in HTML.
Read more »
Popularity: unranked [?]
CherryBlossom
I’ve created a project page for the CherryBlossom programming language. You can check it out here. The interpreter is written in perl.
Popularity: unranked [?]
Introducing CherryBlossom
Over the past month, I’ve been working on a new project. It’s called CherryBlossom, and it’s a way to write programs using haikus. Strictly speaking, CherryBlossom is a brainfuck analog. I actually spent more time writing the obligatory “Hello World” program in CherryBlossom than I did writing the interpreter for the language. The idea behind CherryBlossom is simple. Brainfuck instructions are mapped to words that convey the essence of the Brainfuck instruction. Of course, this is a little subjective and also a little abstract.
Ultimately, it serves as a way to make program code not just functional, but beautiful and artistic. Thus, we introduce a new criteria to programming. Your code must not only be elegant algorithmically, but must also be poetic and artistic (also, since program code consists of haikus, you need to represent your code in sets of 3 lines with the first and last lines having 5 syllables, and the second line 7. That is, conforming to haiku rules). CherryBlossom serves to blend the programmer and the poet into one entity (hopefully with amazing results).
Here is an example of “Hello World!” in CherryBlossom. I have opted to use a spruced up div tag instead of enclosing my beautiful poem in soulless sourcecode tags.
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Popularity: unranked [?]
Akismet flagging everything as spam
If you’ve been commenting on posts and now seeing anything, it’s because Akismet as been flagging all comments as spam. I don’t know why. I think it started after I upgraded WordPress. I’ve turned it off for now. Oh well.
Popularity: unranked [?]
March 29, 2010 Posted by vivin | Nerdy Stuff, Web | akismet, comments, spam, wordpress | Leave a Comment