Auto Increment & Decrement Expressions

The expression syntax, semantics, associativity and precedence are quite identical to the corresponding C and C++ expressions. The operand must be an initialized left value of type integer, char or float. In case of the operand is a char atom, the result type is an integer. Otherwise, the result type is the type of the operand.
General Information
Operators ++
  -
Type unary
Syntaxes expr -
  expr ++
  ++expr
  -expr
Operand Type leftvalue of type integer, char or float.
Result Type see following table
Functions expr - : post-decrementation
  expr ++ : post-incrementation
  ++expr : pre-incrementation
  -expr : pre-incrementation

Possible Operand Combinations
operand type result type
integer integer
float float
char integer

Expression Examples
expression result  
a := 1; a++ 1 initially a equals 1; the result of the evaluation is 1 but after the evaluation, a equals 2
-a 0  
a++ 0 a equals 1 after the evaluation

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