SourceGo

v1.4 beta

Introduction

SourceGo is a transpiler that transforms a subset of Golang code to equivalent SourcePawn. The rationale behind SourceGo is to automate as much of the boilerplate possible when creating SourcePawn plugins.

Purpose

To increase SourcePawn plugin development time by using Golang's streamline engineered syntax.

Features

• Abstracted common types into their own type classes such as float[3] aliasing as Vec3, etc. Here is the current types list and what params it abstracts to:

int     => int
float   => float
bool    => bool
*[]char => char[]
string  => const char[]
*string => char[]
Vec3    => const float[3]
*Vec3   => float[3]

• Pattern matching

Array/slice types will be automatically const unless passed by reference like: *[]type. So having parameters such as []int will be generated as const int[] while *[]int will be generated as int[].

• relative file imports are handled by using a dot . as the first letter

import ".file"

Becomes:

#include "file"

• Multiple return values are supported by mutating them into variable references.

• Range loops for arrays:

var players [MAXPLAYERS+1]Entity
for index, player := range players {
	/// code;
}

for (int index = 0; index < sizeof(players); index++)
{
	int player = players[index];
	/// code;
}

• Switch statements with and without an expression.

// Go
switch x {
	case 1, 2:
	default:
}

switch {
	case x < 10, x+y < 10.0:
		
	default:
}

/// SourcePawn
switch (x)
{
	case 1, 2:
	{
	}
	default:
	{
	}
}

if (x < 10 || x+y < 10.0)
{
}
else
{
}

Expression-less switchs are useful for a more compact if-else-if series.

• Function pointer calls are broken down into manual Function API calling:

func main() {
	CB := OnClientPutInServer
	for i := 1; i<=MaxClients; i++ {
		CB(i)
	}
}

func OnClientPutInServer(client Entity) {}

Becomes:

public void OnPluginStart() {
	Function CB = OnClientPutInServer;
	for (int i = 1; i <= MaxClients; i++) {
		Call_StartFunction(null, CB);
		Call_PushCell(i);
		Call_Finish();
	}
}

public void OnClientPutInServer(int client) {}

• Anonymous Functions (aka Function Literals) are supported:

my_timer := CreateTimer(2.0, func(timer Timer, data any) Action {
	return Plugin_Continue
}, 0, TIMER_REPEAT)

/// SourcePawn
Handle my_timer = CreateTimer(2.0, SrcGoFuncTemp1, 0, TIMER_REPEAT);
...
public Action SrcGoFuncTemp1(Handle hTimer, any data)
{
	return Plugin_Continue;
}

• Inline SourcePawn code using the builtin function __sp__ - for those parts of SourcePawn that just can't be generated (like using new or making a methodmap from scratch).

__sp__ only takes a single string of raw SourcePawn code. Optionally, you can also use a named string constant (it will be generated into the resulting code file, so keep that in mind.)

/// using raw string quotes here so that single & double quotes don't have to be escaped.
var kv KeyValues
__sp__(`kv = new KeyValues("key_value", "key", "val");`)

...
__sp__(`delete kv;`)

• make for making dynamically sized, local arrays:

my_str := make([]char, size)

becomes:

char[] my_str = new char[size];

Planned Features

• Generate Natives and Forwards with an include file for them.
• Abstract, type-based syntax translation for higher data types like StringMap and ArrayList.
• Handle-based Data Structures are abstracted into supportive syntax such where it's value = Map["key"] instead of map.GetValue("key", value);

Goal

Generate SourcePawn source code that is compileable by spcomp without having to modify/assist the generate source code.

Contributing

To submit a patch, file an issue and/or hit up a pull request.

Help

Command line options:

• --debug, -dbg - prints the file's modified AST and pretty-printed version to a file for later checking.

• --force, -f - forcefully generates a SourcePawn source code file, even if errors/issues occurred during transpilation.

• --help, -h - Prints help list.

• --version - Prints the version of SourceGo.

• --no-spcomp, -n - Generates a SourcePawn source-code file without trying to invoke the SourcePawn compiler.

• --verbose, -v - prints additional warnings.

If you need help or have any question, simply file an issue with [HELP] in the title.

Installation

Requirements

Latest Golang version.

Credits

• Nergal - main dev.

License

This project is licensed under MIT License.