weak typing


weakly typed

Strict enforcement of type rules but with well-defined exceptions or an explicit type-violation mechanism.

Weak typing is "friendlier" to the programmer than strong typing, but catches fewer errors at compile time.

C and C++ are weakly typed, as they automatically coerce many types e.g. ints and floats. E.g.

 int a = 5;
 float b = a;

They also allow ignore typedefs for the purposes of type comparison; for example the following is allowed, which would probably be disallowed in a strongly typed language:

 typedef int Date;    /* Type to represent a date */
 Date a = 12345;
 int b = a;       /* What does the coder intend? */

C++ is stricter than C in its handling of enumerated types:

 enum animal {CAT=0,DOG=2,ANT=3};
 enum animal a = CAT;  /* NB The enum is optional in C++ */
 enum animal b = 1;    /* This is a warning or error in C++ */