Our project uses Angelscript to control our VHDL simulations. Since it is currently an internal tool for our company, I'm not able to post any code. However, I can describe how we use it and why we chose Angelscript.

We wanted to be able to create scriptable testbenches without requiring the compilation of complicated testbenches, or a large number of testbenches (as with assertion-based testing). This allows us to create a large number of regression based simulations from a single testbench. We wanted the scripting language to be easy to learn for those involved. Most of our engineers know C, and Angelscript was the best fit (more favorable syntax than Python, Lua, TCL, etc). Also, the scripting engine must be able embeddable into a multi-threaded environment. Since in VHDL things happen concurrently, we wanted to be able to have multiple scripting engines running in parallel without complicated exclusions (as we'd have to do w/ Perl or Python), or stomping on each other (very difficult in Lua). The language must be extensbile. We needed to be able to perform actions in HDL-land from the script. We are using SystemC to model the testbench controller, and coupled with the multiple contexts, we Angelscript provided the easiest and cleanest callback to C++ member functions (messy and painful in Lua).

In the end, Angelscript was an excellent fit. Our users are quite happy, and find it very easy to use. For example, one of our sim scripts look like:

void main()
{
uint readval;

// Do a PCI read from address 0xffff0000
readval = tcon.read(PCI_REQ, 0xffff0000);

// Invert all the bits (a ~ operator would be nice...)
readval = readval ^ 0xffffffff;

// Write back the inverted value
tcon.write(PCI_REQ, 0xffff0000, readval);

// Read it back and verify it is correct
if ( tcon.read(PCI_REQ, 0xffff0000) != readval )
tcon.log("Error: PCI read/modify/write failure!");
}

This is just a tiny example, but shows how we use it (the tcon class is our testbench interface).

We love Angelscript!