Tiny Programming Language Compiler

Compiler for the TINY Programming Language described in Language Description.

• TINY Programming Language
  • Language Description
• TINY Language Regular Expressions
• TINY Language Deterministic Finite Automaton DFA
• TINY Language Context Free Grammar CFG
• TINY Code Samples
  • Sample program includes all 30 rules
  • Sample program in Tiny language – computes factorial

TINY Programming Language

A program in TINY consists of a set of functions (any number of functions and ends with a main function), each function is a sequence of statements including (declaration, assignment, write, read, if, repeat, function, comment, …) each statement consists of (number, string, identifier, expression, condition, …).

Language Description

• Number: any sequence of digits and maybe floats (e.g. 123 | 554 | 205 | 0.23 | …)
• String: starts with double quotes followed by any combination of characters and digits then ends with double quotes (e.g. “Hello” | “2nd + 3rd” | …)
• Reserved_Keywords: int | float | string | read | write | repeat | until | if | elseif | else | then | return | endl
• Comment_Statement: starts with /* followed by any combination of characters and digits then ends with / (e.g. /this is a comment*/ | …)
• Identifiers: starts with letter then any combination of letters and digits. (e.g. x | val | counter1 | str1 | s2 | …)
• Function_Call: starts with Identifier then left bracket “(“ followed by zero or more Identifier separated by “,” and ends with right bracket “)”. (e.g. sum(a,b) | factorial(c) | rand() | … )
• Term: maybe Number or Identifier or function call. (e.g. 441 | var1 | sum(a,b) | …)
• Arithmetic_Operator: any arithmetic operation (+ | - | * | / )
• Equation: starts with Term or left bracket “(“ followed by one or more Arithmetic_Operator and Term. with right bracket “)” for each left bracket (e.g. 3+5 | x +1 | (2+3)*10 | …)
• Expression: may be a String, Term or Equation (e.g. “hi” | counter | 404 | 2+3 | …)
• Assignment_Statement: starts with Identifier then assignment operator “:=” followed by Expression (e.g. x := 1 | y:= 2+3 | z := 2+3*2+(2-3)/1 | …)
• Datatype: set of reserved keywords (int, float, string)
• Declaration_Statement: starts with Datatype then one or more identifiers (assignment statement might exist) separated by coma and ends with semi-colon. (e.g. int x; | float x1,x2:=1,xy:=3; | …)
• Write_Statement: starts with reserved keyword “write” followed by an Expression or endl and ends with semi-colon (e.g. write x; | write 5; | write 3+5; | write “Hello World”; | …)
• Read_Statement: starts with reserved keyword “read” followed by an Identifier and ends with semi-colon (e.g. read x; | …)
• Return_Statement: starts with reserved keyword “return” followed by Expression then ends with semi-colon (e.g. return a+b; | return 5; | return “Hi”; | …)
• Condition_Operator: ( less than “<” | greater than “>” | is equal “=” | not equal “<>”)
• Condition: starts with Identifier then Condition_Operator then Term (e.g. z1 <> 10)
• Boolean_Operator: AND operator “&&” and OR operator “||”
• Condition_Statement: starts with Condition followed by zero or more Boolean_Operator and Condition (e.g. x < 5 && x > 1)
• If_Statement: starts with reserved keyword “if” followed by Condition_Statement then reserved keyword “then” followed by set of Statements (i.e. any type of statement: write, read, assignment, declaration, …) then Else_If_Statment or Else_Statment or reserved keyword “end”
• Else_If_Statement: same as if statement but starts with reserved keyword “elseif”
• Else_Statement: starts with reserved keyword “else” followed by a set of Statements then ends with reserved keyword “end”
• Repeat_Statement: starts with reserved keyword “repeat” followed by a set of Statements then reserved keyword “until” followed by Condition_Statement
• FunctionName: same as Identifier
• Parameter: starts with Datatype followed by Identifier (e.g. int x)
• Function_Declaration: starts with Datatype followed by FunctionName followed by “(“ then zero or more Parameter separated by “,” then “)” (e.g. int sum(int a, int b) | …)
• Function_Body: starts with curly bracket “{” then a set of Statements followed by Return_Statement and ends with “}”
• Function_Statement: starts with Function_Declaration followed by Function_Body
• Main_Function: starts with Datatype followed by reserved keyword “main” then “()” followed by Function_Body
• Program: has zero or more Function_Statement followed by Main_Function

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TINY Language Regular Expressions

digit ::= 0|1|2|3|4……|9

letter ::= [a-z][A-Z]

Number ::= digit.?digit

String ::= “(letter|digit)*”

Reserved_Keywords ::= int | float | string | read | write | repeat | until | if | elseif | else | then | return | endl

Comment ::= /*String*\/

Identifier ::= letter (letter | digit)*

Term ::= Number | Identifier | Function_Call

Arithmatic_Operator ::= + | - | * | /

Equation ::= (Term (Arithmatic_Operator (Equation | Term))+) | (( Term Arithmatic_Operator ( Equation | Term) )) (Arithmatic_Operator (Term | Equation))*

Expression ::= String | Term | Equation

Datatype ::= int | float | string

Condition_Operator ::= < | > | = | <>

Boolean_Operator ::= && | \|\|

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TINY Language Deterministic Finite Automaton DFA

• Strings

• Reserved Words

• Operators

• Identifiers

• Constants

• Comments

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TINY Language Context Free Grammar CFG

• Program → Program_Function_Statement Main_Function

• Main_Function → Data_Type main ( ) Function_Body

• Program_Function_Statement → Function_Statement Program_Function_Statement | ɛ

  • Function_Statement → Function_Declaration Function_Body

  • Function_Declaration → Data_Type Function_Name ( Function_Parameters )

  • Datatype → int | float | string

  • Function_Name → identifier

  • Function_Parameters → Data_Type Identifier More_Parameters | ɛ

  • More_Function_Parameters → , Data_Type Identifier More_Function_Parameters | ɛ

  • Function_Body → { Statements Return_Statement }

• Statements → State Statements | ɛ

  • Statement → Function_Call | Assignment_Statement | Declaration_Statement | Write_Statement | Read_Statement | If_Statement | Repeat_Statement

• Function_Call → Identifier ( Parameters) ;

  • Parameters → Expression More_Parameters | ɛ
  • More_Parameters → , Expression More_Parameters | ɛ

• Assignment_Statement → Identifier := Expression

• Expression → String | Term | Equation

• Term → number | identifier | Function_Call

• Equation → Term Operator_Equation | (Equation) Operator_Equation

• Operator_Equation → Arthematic_Operator Equation Operator_Equation | ε

  • Arthematic_Operator → plus | minus | divide | multiply

• Declaration_Statement → Data_Type Identifier Declare_Rest1 Declare_Rest2 ;

  • Declare_Rest1 → , identifier Declare_Rest1 | ɛ

  • Declare_Rest2 → Assignment_Statement | ɛ

• Write_Statement → write Write_Rest ;

  • Write_Rest → Expression | endl

• Read_Statement → read identifier ;

• If_Statement → if Condition_Statement then Statements Other_Conditions

  • Condition_statement → Condition

  • Condition → identifier Condition_Operator Term More_Conditions

  • Condition_Operator → less_than | greater_than | not_equal | equal

  • More_Conditions → and Condition | or Condition| ɛ

  • Other_Conditions → Else_if_Statement | Else_statement | end

• Else_if_Statement → elseif Condition_statement then Statements Other_Conditions

• Else_statement → else Statements end

• Repeat_Statement → repeat Statements untill Condition_statement

• Return_Statement → return Expression ;

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TINY Code Samples

Sample program includes all 30 rules

int sum(int a, int b)
{
	return a + b;
}
int main()
{
	int val, counter;
	read val;

	counter := 0;

	repeat                                                                                
		val := val - 1;
		write "Iteration number [";
		write counter;
		write "] the value of x = ";
		write val;
		write endl;                          
		counter := counter+1;                                                      
	until val = 1

	write endl;

	string s := "number of Iterations = ";
	write s; 

	counter := counter-1;

	write counter;

	/* complicated equation */    
	float z1 := 3*2*(2+1)/2-5.3;
	z1 := z1 + sum(a,y);

	if  z1 > 5 || z1 < counter && z1 = 1 
	then 
		write z1;
	elseif z1 < 5 
	then
		z1 := 5;
	else
	    z1 := counter;
	end

	return 0;
}

Sample program in Tiny language – computes factorial

/* Sample program in Tiny language – computes factorial*/
int main()
{
	int x;
	read x; /*input an integer*/
	if x > 0 /*don’t compute if x <= 0 */
	then 
		int fact := 1;

		repeat
			fact := fact * x;
			x := x – 1;
		until x = 0

		write fact; /*output factorial of x*/
	end
	return 0;
}