New debugging stuff!

Today I improved debugging a bit.

First, when you step through a program, QuiteBASIC will scroll the program text so that the current line is visible and it will highlight the line number so it is easy to see.

Second, I added a new button "go to cursor". To use it, place the cursor somewhere in your program where you want to stop execution and the click the button. QuiteBASIC will run normally until it reaches the line with the cursor.

This stuff had been quite often requested, but it was a little tricky to pull off in JavaScript. Anyway, here it is now!

Something is up in Ardmore, Oklahoma

The last two weeks, the traffic has increased a lot from this town. Not weekends though, only weekdays. Citizens of Ardmore, welcome to QuiteBASIC!

IE9 and Chrome are neck-and-neck!

QuiteBASIC is quite a challenge for web browsers. The BASIC interpreter runs in Javascript and the DOM gets thoroughly exercised by the graphics (a HTML table where each pixel is a cell). Until today Chrome always had an edge on IE and other browsers.

But today I installed IE9 RC and it is fast!

Chrome 9 and IE9 are actually virtually neck-and-neck in terms of speed on all projects I tried with IE9 just a tiny bit faster.

The Brute force solution for the Eight Queens problem runs in 6 seconds in both bowsers.

The Bifurcations Math project runs in 6 seconds on IE9 and 7 seconds on Chrome.

And the picture below shows how far the Mandelbrot program got in one minute -- slightly longer (that means faster) on IE9.

In the picture it is also easy to appreciate the compact chrome of IE9. It takes much less screen real-estate than Chrome.

Starting 2011 with a UI Refresh

It has been quiet here for a while, but today QuiteBASIC gets its first major UI refresh since it was launched back in 2006!

The new UI is more compact and is designed to make it easier to work on writing programs. Under the hood are also some exciting changes that lay the foundation for new features that will roll out later this year...

There are also some bug-fixes and full support for Chrome which didn't exist in 2006!

Quite BASIC Video Introduction

Compatibility Step 7

Another step towards running "Hunt the Wumpus" on Quite BASIC! :)

Today I added conditional GOTO to the language. I did it with mixed feelings because it is one ugly construct, but many early BASIC programs did use it.

So, now you can do things like:
10 LET R = 1 + RND(3)
20 ON R GOTO 100,200,300
...

That little code snippet will randomly make the program go to either line 100, 200, or 300.

Oh, and I also added the INT(x) function. It is the same as the existing FLOOR(x), but INT(x) is the name that classic BASIC programs used.

Compatibility Step 6 -- Multi dimensional Arrays

This one was not straight forward because javascript doesn't have a simple syntactic construct to create a multi dimensional arrays. As of today though, QuiteBASIC has just that. For example:

10 DIM A(5,6,4)

declares a 3D array.

The array can then be used in LET commands and in expressions just like you expect it to. For example:

20 LET A(1,2,3) = 64
30 PRINT SQR(A(1,2,3))

will print 8.

This only works with the DIM command. The ARRAY command just declares a 1D array of dynamic size. And this only works with the parenthesis syntax for array indices. So A[1,2,3] is a syntax error.

I also added the TAB(x) function which is typically used in PRINT commands to format the output. For example:

40 PRINT TAB(5); "Hello!"

will print five spaces followed by "Hello!".