Abaci scripting/programming language

About

Abaci is a JIT-compiled interactive scripting language based on the LLVM toolchain. It is intended to be easy to learn by novice programmers and able to be translated into other natural (written) languages if desired. The interactive environment started by default compiles user input in real-time and executes it quickly. When called with a textual script file as an argument, this file is compiled and executed as a batch process.

Pre-requisites

To build this project requires:

• A C++ compiler, tested only with g++ version 12.2.0, Visual Studio 2022 C++ and clang++ version 14.0.6
• The LLVM development libraries, built against version 14.0
• The Boost headers, specifically Boost Spirit X3 in Boost 1.74
• Headers and link-library of fmt built against version 10.2.1

This project was developed using Debian current stable (Bookworm).

Building

To create the executable abaci in a build sub-directory of the project source files under Linux use:

mkdir build && cd build
cmake ..
make

To build with Clang it may be necessary to use C++20 (instead of C++23) in the CMakeLists.txt:

set(CMAKE_CXX_STANDARD 20)

To build against C++23's <format> and <print> headers (if available) instead of fmt, use cmake .. -DABACI_USE_STD_FORMAT=1".

To build with older Boost headers, in particular version 1.74, use cmake .. -DABACI_USE_OLDER_BOOST=1 to avoid compilation errors for parser/Parse.cpp.

Run ./abaci without arguments to enter an interactive session, or with a source filename as the single argument to execute a script.

To create the executable abaci.exe under Windows, using CMake and VS 2022, first build LLVM from source. Then make a build directory at the same level as src and issue:

cmake.exe .. -A x64 -Thost=x64 -DLLVM_DIR=C:\Users\<path_to>\llvm-19.1.1\lib\cmake\llvm -DBoost_INCLUDE_DIR=C:\Users\<path_to>\boost_1_86_0 -DABACI_USE_STD_FORMAT=1

Then load Abaci.sln into VS 2022 and select build type "Release" before building.

(Replace <path_to> in each case with the correct path to LLVM and Boost.)

Status

This project is currently under heavy development and should be considered pre-alpha. Current plans for features to be added include:

• Broken parsing for method calls to be investigated (completed)
• Homogeneous lists (completed)
• String indexing
• Closures (major changes are likely needed)
• Error reporting tidied up (completed) with more accurate location reporting (investigated and considered not possible)
• Memory leaks closed (completed)
• Unit tests of Abaci code (in progress)

Please raise feature requests (and bugs found) as issues.

Language overview

Assignments

Constant assignment

let a = 3.3

Variable assignment

let b <- 1

Variable reassginment

b <- 2

Tuple assignment

class mytuple(x, y, z) endclass
let c <- mytuple(1, 2.2, "hi")
print c.z

Array assignment (not yet implemented)

let d = [ 2, 3, 5, 7, 11 ]
print !d
print d[3]
d[3] <- nil
print !d
print d[3]

Math operators

+, -, *, / (always creates floating point number), % (integer only), // (floor division), ** (exponentiation)

Comparison operators

= (same as assign constant, but in different context), !=, <, <=, >=, >, </<= value </<=

Decisions

if *condition*
    statements...
endif

if *condition*
    statements...
else
    statements...
endif

case *expression>
  when *match1* statements...
  when *match2*, *match3*,... statements...
  else  # this is optional
  statements...
endcase

Loops

while *condition*
  statements...
endwhile

repeat
  statements...
until *condition*

Type conversions

let a <- 2.2
print str(a) + " floating"
print int(a)
print real(3 + 4j)
print imag(3 + 4j)
print float("3.14") * 2.0

Function definition

let f(x) -> x + 1
print f(2)

fn g() 
  let x <- 0
  while 0 <= x < 10
    print x
    x <- x + 1
  endwhile
endfn

g()

Function call

b <- f(b)
g()

Class definition

class c(x,y)
  fn i(d)
    print this.x * d
    print this.y * d
  endfn
endclass

let f <- c(2.2,3j)
f.i(2.5)

Comments

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Version history

• 0.0.1 (2024-Sep-07): First release of code for this project, many known bugs and problems

• 0.0.2 (2024-Sep-16): Second release with many changes and fixes, no known bugs

• 0.0.3 (2024-Sep-19): Third release with Clang compatibility and more fixes

• 0.0.4 (2024-Sep-21): Fourth release with stability and error message improvements

• 0.0.5 (2024-Sep-28): Fifth release with list support and many other improvements

• 0.0.6 (2024-Oct-04): Sixth release with code improvements and support for different builds

• 0.1.1 (2024-Oct-22): Seventh release with small syntax changes and unit testing capability

License

All source code and documentation released under the MIT License, ©2024 Richard Spencer