C Family Language using AST approach (DEMO)

This is my attempt to create a C family programming language. The language itself has simple syntax similar to C#.

The approach is taken from the book Crafting Interpriters by Robert Nystrom.

You are very welcomed to contribute.

Features

Syntax

Variable declaration

int a = 10;
string b = "string example";
char c = "c";
double d = 10.3;
float f = 10.3;
bool e = true;
int[] arr1 = {1, 2, 3, 4};
double[] arr2 = {1.0, 2.0, 3.0, 4.0};
float[] arr3 = {1.0, 2.0, 3.0, 4.0};
string[] arr4 = {"1", "2", "3", "4"};
char[] arr5 = {"1", "2", "3", "4"};
bool[] arr6 = {true, false, true, false};

Print

WriteLine("Test 1");

If-else statement

bool testBool = true;
bool testBool2 = false;

if (testBool && testBool2 || false) {
    WriteLine("if went to true");
} else {
    WriteLine("if went to false");
}
// prints: if went to false

Function declaration/call

Note: you can declare functions with type int, string etc., but there is no return handling there yet.

void something() {
    WriteLine("Hello");
}
something(); // prints "Hello"

// ...
int something1() {}
string[] something2() {}
// ...

Class declaration/ Inheritence

Note: there is no proper init handling yet.

class Some {
    int sum(int a, int b) {
        return a + b;
    }
}

class Something: Some {
    void test() {
        WriteLine("Calling parent class method:");
        int sumResult = base.sum(10, 5);
        WriteLine(sumResult);
    }
}
Something().test();
// Calling parent class method:
// 15

While loop

int count = 0;
while (count < 5) {
    count = count + 1;
}

Supported operators

+
-
*
/
=
+=
-=
/=
*=
()
!=
!
<
<=
>
>=
==

Error Handling

The programm handles a variety of possible errors.

Here are some of them:

Syntax errors
Type errors
Index out of range
Unnown variable

Usage & Preview

Write the code in our language in file Examples/language.
Run the project.
You will be able to see the results of the script in terminal. Also in the Examples directory you can find the represantation of the code in AST, RPN and C++.

Input code

int a = 10;
a = 20;
string b = "20";
char abs = "c";

int count = 0;
void something() {
    WriteLine("Hello");
}

WriteLine("Test calling function that prints Hello");
something();
int c = 10;
WriteLine("Test: 10 + 10:");
WriteLine(a + c);
int[] arr = { 1, 2, 3, 2, 3, 4 };
WriteLine("Printing arr = [1, 2, 3, 2, 3, 4]:");
WriteLine(arr);
WriteLine("Printing arr[1]:");
WriteLine(arr[1]);
WriteLine("Changing arr[1] to 20:");
arr[1] = 20;
WriteLine(arr[1]);

bool testBool = true;
bool testBool2 = false;

if (testBool && testBool2 || false) {
    WriteLine("if went to true");
} else {
    WriteLine("if went to false");
}

int count1 = 2;
while (count < 5) {
    count += 1;
    count1 *= 2;
}
WriteLine(count);
WriteLine(count1);

class Some {
    int sum(int a, int b) {
        return a + b;
    }
}

class Something: Some {
    void test() {
        WriteLine("Calling parent class method:");
        int sumResult = base.sum(10, 5);
        WriteLine(sumResult);
    }
}
Something().test();

Interpreter Result

Test calling function that prints Hello
Hello
Test: 10 + 10:
30
Printing arr = [1, 2, 3, 2, 3, 4]:
[1, 2, 3, 2, 3, 4]
Printing arr[1]:
2
Changing arr[1] to 20:
20
if went to false
5
64
Calling parent class method:
15

AST Printer

int a = 10
a = 20
string b = "20"
char abs = "c"
int count = 0
void something () (((PRINT "Hello")) )
(PRINT "Test calling function that prints Hello")
something CALL
int c = 10
(PRINT "Test: 10 + 10:")
(PRINT a + c)
int[] arr = ( ARRAY LENGTH(6) 1 2 3 2 3 4 )
(PRINT "Printing arr = [1, 2, 3, 2, 3, 4]:")
(PRINT arr)
(PRINT "Printing arr[1]:")
(PRINT GET arr INDEX(1))
(PRINT "Changing arr[1] to 20:")
arr INDEX(1) = 20
(PRINT GET arr INDEX(1))
bool testBool = true
bool testBool2 = false
IF false || testBool2 && testBool THEN ( (PRINT "if went to true") ) ELSE ( (PRINT "if went to false") ) END
int count1 = 2
WHILE count < 5 DO ( count += 1 count1 *= 2 ) END
(PRINT count)
(PRINT count1)
( CLASS Some (int sum (int a int b) (((RETURN a + b)) )) )
( CLASS Something < PARENTCLASS Some (void test () (((PRINT "Calling parent class method:")) (int sumResult = BASE.sum 10 5 CALL) ((PRINT sumResult)) )) )
Something CALL test CALL

RPN AST

a 10 = int
a 20 =
b "20" = string
abs "c" = char
count 0 = int
something FUNCTION(0) void PROC_START "Hello" PRINT PROC_END
"Test calling function that prints Hello" PRINT
something CALL
c 10 = int
"Test: 10 + 10:" PRINT
a c + PRINT
arr ( 1 2 3 2 3 4 LENGTH(6) ARRAY ) = int[]
"Printing arr = [1, 2, 3, 2, 3, 4]:" PRINT
arr PRINT
"Printing arr[1]:" PRINT
arr INDEX(1) GET PRINT
"Changing arr[1] to 20:" PRINT
arr INDEX(1) 20 =
arr INDEX(1) GET PRINT
testBool true = bool
testBool2 false = bool
false testBool2 testBool && || MARK_1 COND_JUMP BLOCK_START "if went to true" PRINT BLOCK_END MARK_2 UNCOND_JUMP MARK_1: BLOCK_START "if went to false" PRINT BLOCK_END MARK_2:
count1 2 = int
count 5 < LOOP_MARK COND_JUMP BLOCK_START count 1 += count1 2 *= BLOCK_END LOOP_MARK:
count PRINT
count1 PRINT
( Some CLASS (sum a int b int FUNCTION(2) int PROC_START a b + RETURN PROC_END) )
( Something CLASS < Some PARENTCLASS (test FUNCTION(0) void PROC_START "Calling parent class method:" PRINT sumResult BASE.sum 10 5 CALL = int sumResult PRINT PROC_END) )
Something CALL test CALL

C++ Converter