Getting Started

Get The DQ Compiler

DQ programs are compiled with dq-comp. For single-file experiments, the companion dq-run tool compiles a .dq file and immediately runs the result.

The easiest way to get the compiler is to download a release package from the project's GitHub releases page:

https://github.com/nvitya/dq-lang/releases

After extracting or installing a release package, make sure the compiler tools are on your PATH:

dq-comp --version
dq-run --help

If there is no release package for your platform yet, build the compiler from source by following Getting the DQ Compiler.

First Program

DQ programs are written in .dq files.

use print

function *Main() -> int:
    PrintLn("hello from DQ")
    return 0
endfunc

Run with:

dq-run hello.dq

dq-run first invokes dq-comp, which compiles hello.dq into ./hello, and then runs the created executable:

dq-comp -g -O0 hello.dq
./hello

Program Entry

A program entry point is a special function named *Main.

function *Main() -> int:
    return 0
endfunc

The return value becomes the process exit code.

Arguments

Program arguments are available through the implicit runtime module.

use print

function *Main() -> int:
    for i : int = 0 count ArgCount():
        PrintLn("arg {} = {}", [i, ArgStr(i)])
    endfor
    return 0
endfunc

Run with arguments:

dq-run args.dq -- one two

The -- separator is useful when program arguments may look like compiler options.

Standard Packages

Standard modules are imported with use.

use print
use strutils
use file
use json

The compiler searches its built-in standard package roots first, then any roots added with --pkg-path.

Optimization and Debugging

Code optimization means the compiler spends extra work improving the generated machine code. Optimized code can make debugging harder because the generated machine code may no longer follow the source code line by line.

The -O0 option turns off optimization. The -O3 --lto combination enables the highest optimization level and link-time optimization.

To debug code or see error backtraces with source line information, pass -g when compiling.

When no compiler options are supplied, dq-run uses -g -O0, which is a good debugging default and enables useful source locations in runtime backtraces. dq-comp compiles with -O1 optimization and no debug info by default.

For fastest running code, invoke dq-run or dq-comp with -O3 --lto:

dq-run -O3 --lto examples/benchmarks/binary_trees_dq.dq 20