cicinlang 0.1.2

A general purpose, procedural, interpreted programming language made using Python

Cicinlang

Welcome to the Cicinlang repo. Cicinlang is a toy programming language created using Python. It is a general-purpose, procedural, interpreted language that includes support for loops, conditional statements, variables and functions (including partial support for anonymous functions).

This documentation serves as a guide on the basics of Cicinlang syntax.

How To Use

First, install cicinlang using pip:

pip install cicinlang

Then, invoke the cicinlang script with the path of the file you want to execute:

cicinlang <path_to_file>

Arithmetic and Logical Expressions

Cicinlang includes support for the following arithmetic operations:

• Addition (including unary +)
• Subraction (including unary -)
• Multiplication ( * )
• Division ( / )
• Exponentiation ( ^ )
• Parentheses ( '(' , ')' )

The following logical operations are also supported:

• ASSIGNMENT ( = )
• OR ( or )
• AND ( and )
• NOT ( not )
• EQUALS ( == )
• NOT EQUALS ( != )
• GREATER THAN ( > )
• GREATER THAN OR EQUAL TO ( >= )
• LESS THAN ( < )
• LESS THAN OR EQUAL TO ( <= )

In Cicinlang, 0, 0.0 and "" represent False, and all other strings and numbers represent True.

The operator precedence of Cicinlang is as follows:

Position	Operations
1	Function Calls, not, Unary +/-, ()
2	^
3	* , /
4	<, <=
5	>, >=
6	==, !=
7	and
8	or
9	=

A few examples or arithmetic and logical expressions:

# Evaluated as  ( 1 + ( 2 * 3 ) - ( 4 ^ 5 ) ) or ( 0 <= 5 )
1 + 2 * 3 - ( 4 ^ 5 ) or 0 <= 5;

# Evaluated as ( ( 1 / 2 ) / 3 ) and ( not ( 6 or ( 7 != 8 ) ) )
1 / 2 / 3 and not 6 or 7 != 8;

Variables

To declare and initialize a variable, use the 'var' keyword. To use an existing variable, just reference its name. To re-define a variable, simply define it without the 'var' keyword.

# Declaring and initializing
var a = 5;
var b = "hello github";
var c = ( a, b ) => { return a + b; }

# Referencing
print( str( a ) + b );

# Re-defining
a = 7.1; 
b = 8;

Note: Variables in Cicinlang are dynamically typed. This means a variable storing a string can be redefined to store a number.

In Cicinlang, variable assignment statements are expressions that return the assigned value.

var c = 10;
c = var a = 7;

# After the second statement, the value of c is updated to 7, and a new variable a is created with value 7

Data Types

Cicinlang supports the following data types:

• Number ( integer and floats )
• String
• None

One thing to note: None cannot be explicity defined. A variable can be set to None only if it is set to a function output and the function returns nothing.

var c = () { print( 5 ); } # This function returns nothing

var d = c(); # The value of d will be None

Strings

Cicinlang includes support for strings. They can be single-quoted or double quoted.

var s1 = 'Single quoted string';
var s2 = "Double quoted string";

Strings support the following operations:

• Binary '+' ( Causes concatenation )
• not
• and
• or

An empty string (i.e. a string with 0 characters) is a false-y value in Cicinlang

var gg = "hello" + " world"; # gg will be "hello world"
var gg2 = not ""; # gg2 will be 1
var gg3 = "" and "hello"; # gg3 will be 0

For the logical AND and logical OR operations, strings and numbers can be combined.

var gg4 = "hello" and 5; # gg4 will be 1 since both "hello" and 5 are truth-ey values

If-Statements

If-statements in Cicinlang are written as follows:

var level = 6;

if ( level < 7 ) {
    print( "Level is low." );
}

elif ( level < 10 ) {
    print( "Level is high." );
}

else {
    print( "Level is very high." );
}

The condition inside the if statement can be any valid expression that evaluates to a number.

One quirk of if-statements in Cicinlang is that the else block has to be included even if there are no instructions inside it. For example, the following if-statement with no else-instructions has to be written like:

var else_test = 0;

if ( else_test ) {
    print( "Zero" );
}

else {} # This part has to be included even if empty

For-loops

for( initialize_expr; condition_expr; update_expr ) {
    # Loop body
}

• 'initialize_expr' can be any valid expression within the language. For example, it can be a variable assignment, a whole if-chain, or any other valid statement.

• 'initialize_expr' can also be left empty. In that case, the syntax is as follows:

for( ; condition_expr; update_expr ) {
    # Loop body
}

• 'condition_expr' HAS to evaluate to a value. For example, it can be:

  • Arithmetic or logical expressions with strings and numbers
  • Variable assignments

• The for-loop will continue as long as the condition_node evaluates to 0

• Like 'initialize_expr', 'update_expr' can be any valid expression inside the language

Example for-loop

for ( var i = 0; i < 5; i = i + 1 ) {
    print( "Current value of i:" );
    print( i );
}

As of July 2023, Cicinlang does not include support for while loops.

Functions

Functions are defined as follows:

var get_sum = ( val1, val2 ) {
    return val1 + val2;
}

var sum = get_sum( 4, 5 );

print( sum ); # Prints 9

• Unlike other statements in Cicinlang, variable assignment statements that defined functions don't have to end with a semicolon

• Fucntions can have 0 or more arguments passed into them

• Functions can also be returned by other functions:

var ret_func = () {
    return ( a, b ) { return a + b; }
}

var c = ret_func();

print( c( 1, 2 ) ); # Prints 3

• Before calling a function, it has to be put inside a variable first:

# () { return ( a ) { print( a ); } }()( 23 ); # THIS IS NOT VALID 

var func1 = () { return () { ( a ) { print( a ); } } }

# func1()( 23 ); # THIS IS NOT VALID

# This is valid
var e = func1();
e( 5 );

Comments

# You can write comments by typing text after a hashtag
# Multi-line comments are not supported yet

var z = 10; # You can also write comments like this

Print Statements

print( 5 ); # 5
print( 10 + 5 ); # 15
print( "a" + " cat" ); # a cat
print( 0 or "a" ); # 1

• Prints a statement and moves the cursor to the next line ( keeping the cursor in the same line is not currently supported )

• Functions cannot be printed unless they are stringified ( discussed later )

Stringify Statements

• The below statement will throw and error:

var a = 5 + " is an odd number.";

• Strings and numbers cannot be concatenated in Cicinlang. Hence, one might ask, "How can I join numbers and strings in statements to be able to print them?" Stringification is the answer:

var a = str( 5 ) + " is an odd number.";

• The above statement will not throw an error

• To stringify an expression, simply type str() and put the expression inside the parentheses.

Input Statements

• Cicinlang supports taking user input. There are two relevant functions for user input:

  • input_num( message ): First, 'message' is printed ( if given ). Then, a string input is taken from the user, and the program tries to convert it into a number. If it cannot do so, Cicinlang throws an error. The expression then evaluates to that number.

  • input_str( message ): First, 'message' is printed ( if given ). Then, a string input is taken from the user. The expression then evaluates to that string.

var name = input_str( "Enter your name: " );
var age = input_num( "Enter your age: " );

print( name + " is " + str( age ) + " years old." );

Known Issues

• When errors are thrown, the line and column numbers might not always match the exact spot of the error

• In some cases, Python exceptions might be thrown instead of Cicinlang exceptions. This might be since those Python exceptions were not caught, or because there was a flaw with the implementation of the lexer, parser, or interpreter