Static Type Binding

• An 1($) is a statement in a program that lists variable names and specifies that they are a particular type.
• An 2($) is a means of associating variables with types through default conventions, rather than declaration statements.

Most widely used programming languages that use static type binding exclusively and were designed since the mid-1960s require explicit declarations of all variables.

An identifier that appears in a program that is not explicitly declared is implicitly declared according to the following convention: If the identifier begins with one of the letters I, J, K, L, M, or N, or their lowercase versions, it is implicitly declared to be Integer type; otherwise, it is implicitly declared to be Real type.

Many Fortran programmers now include the declaration Implicit none in their programs.  This declaration instructs the compiler to

Some of the problems with implicit declarations can be avoided by requiring names for specific types to begin with particular special characters.  In Perl

1. Any name that begins with $ is a 1($), which can store either a string or a numeric value.
2. If a name begins with @, it is an 2($).
3. If it begins with a %, it is a 3($).

• var sum = 0;1($)
• var total = 0.0;2($)
• var name = "Fred";3($)