semantic-checklist.md

semantic checker checklist

main function

• have and only have one main function with return type int.
• no parameters.
• return statement can be ignored.
• if has return, can only return int.
• main can't be used as class name or other functions' name.

Control Flow

• break and continue can only be used in for and while loop.
• if's condition can only be bool.
• for-loop condition can only be bool.

Function Declaration

• return type match declaration.
• non-void function must have return statement.
• this usage : regarded as a type.

lambda function

• parameters match arguments.
• should have a return statement.
• definition : right associative.
• check the scope's var.

class declaration

• name can't be builtin types.
• constructor : no return statement, no parameters.
• constructor : same name.
• other function name can't be the same as constructor.

definition errors

• no void type for vars.
• var can't support back reference.
• class, function support back reference.
• undefined being used.
• Duplicate for vars,function,class, which means the three can't have the same name.

Var declaration

• variable can't be void.
• creator can't be void.

Type Handling

• every expression has a type.
• any conversion is undefined behavior.
• assignment match.
• field,arugments,method match definition.

dimension Handling

• creator has a type with dimension.
• creator format (from left to right).
• dimension set.
• subscript expression.

Operator expression

• ADD,SUB,... can only be used on some specific types.
• logic operator can only be used on bool.

Left Value

• literal value,function call can't be left value.
• this can't be assigned.
• a++ return a right value.
• a++,++a : a need to be left value.
• function call can't be left value.

Others

• subscript can only be int.
• null can only be assigned to reference type.