Description CMSC 430 Project 3 The third project involves modifying the attached interpreter so tha ...

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Description CMSC 430 Project 3 The third project involves modifying the attached interpreter so that it interprets programs for the complete language. You may convert all values to double values, although you can maintain their individual types if you wish. When the program is run on the command line, the parameters to the function should be supplied as command line arguments. For example, for the following function header of a program in the file text.txt: function main a: integer, b: integer returns integer; One would execute the program as follows: $ ./compile < test.txt 2 4 In this case, the parameter a would be initialized to 2 and the parameter b to 4. An example of a program execution is shown below: $ ./compile < test.txt 2 4 1 function main a: integer, b: integer returns integer; 2 c: integer is 3 if a > b then 4 a rem b; 5 else 6 a ** 2; 7 endif; 8 begin 9 case a is 10 when 1 => c; 11 when 2 => (a + b / 2 - 4) * 3; 12 others => 4; 13 endcase; 14 end; Compiled Successfully Result = 0 After the compilation listing is output, the value of the expression which comprises the body of the function should be displayed as shown above. The existing code evaluates some of the arithmetic, relational and logical operators together with the reduction statement and integer literals only. You are to add the necessary code to include all of the following: ? Real and Boolean literals ? All additional arithmetic operators ? All additional relational and logical operators ? Both if and case statements ? Functions with multiple variables ? Functions with parameters This project requires modification to the bison input file, so that it defines the additional the necessary computations for the above added features. You will need to add functions to the library of evaluation functions already provided in values.cc. You must also make some modifications to the functions already provided.The fourth project involves modifying the semantic analyzer for the attached compiler by adding checks for semantic errors. The static semantic rules of this language are the following: Variables and parameter names have local scope. The scope rules require that all names be declared and prohibit duplicate names within the same scope. The type correspondence rules are as follows: ? Boolean expressions cannot be used with arithmetic or relational operators. ? Arithmetic expressions cannot be used with logical operators. ? Reductions can only contain numeric types. ? Only integer operands can be used with the remainder operator. ? The two statements in an if statement must match in type. No coercion is performed. ? All the statements in a case statement must match in type. No coercion is performed. ? The type of the if expression must be Boolean. ? The type of the case expression must be Integer ? A narrowing variable initialization or function return occurs when a real value is being forced into integer. Widening is permitted. ? Boolean types cannot be mixed with numeric types in variable initializations or function returns. Type coercion from an integer to a real type is performed within arithmetic expressions. You must make the following semantic checks. Those highlighted in yellow are already performed by the code that you have been provided, although you are must make minor modifications to account for the addition of real types and the need to perform type coercion and to handle the additional arithmetic and logical operators. ? Using Boolean Expressions with Arithmetic Operator ? Using Boolean Expressions with Relational Operator ? Using Arithmetic Expressions with Logical Operator ? Reductions containing nonnumeric types ? Remainder Operator Requires Integer Operands ? If-Then Type Mismatch ? Case Types Mismatch ? If Condition Not Boolean ? Case Expression Not Integer ? Narrowing Variable Initialization ? Variable Initialization Mismatch ? Undeclared Variable ? Duplicate Variable ? Narrowing Function Return This project requires modification to the bison input file, so that it defines the additional semantic checks necessary to produce these errors and addition of functions to the library of type checking functions already provided in types.cc. You must also make some modifications to the functions provided. You need to add a check to the checkAssignment function for mismatched types in the case that Boolean and numeric types are mixed. You need to also add code to the checkArithmetic function to coerce integers to reals when the types are mixed and the error message must be modified to indicate that numeric rather than only integer types are permitted. The provided code includes a template class Symbols that defines the symbol table. It already includes a check for undeclared identifiers. You need to add a check for duplicate identifiers. Like the lexical and syntax errors, the compiler should display the semantic errors in the compilation listing, after the line in which they occur. An example of compilation listing output containing semantic errors is shown below: 1 -- Test of Multiple Semantic Errors 2 3 function test a: integer returns integer; 4 b: integer is 5 if a + 5 then 6 2; 7 else 8 5; 9 endif; Semantic Error, If Expression Must Be Boolean 10 c: real is 9.8 - 2 + 8; 11 d: boolean is 7 = f; Semantic Error, Undeclared f 12 begin 13 case b is 14 when 1 => 4.5 + c; 15 when 2 => b; Semantic Error, Case Types Mismatch 16 others => c; 17 endcase; 18 end; Lexical Errors 0 Syntax Errors 0 Semantic Errors 3 You are to submit two file