Variable = s-variable | t-variable | e-variable | v-variable. s-variable = "s" [ "." ] VariableIndex. t-variable = "t" [ "." ] VariableIndex. v-variable = "v" [ "." ] VariableIndex. e-variable = "e" [ "." ] VariableIndex. VariableTypeDesignator = "s" | "t" | "v" | "e". VariableIndex = IdentifierTail.
A variable consists of a variable type designator followed by a variable index. The type
designator and the index may be separated by an optional dot. For example:
Hence,
Adjacent variables must be separated. For example,
The index of a variable may be omitted, which means that the index is unique and different
from the indices of all other variables appearing in the program. Thus, for example, if the
variables
Variables are distinguished into four classes: s-variables, t-variables, v-variables, and e-variables, the class of a variable being determined by the type designator.