GOTO statement

PMP supports program label and branch statements:

label-item-declaration = label-item ":" .
goto-statement = GOTO label-item .
label-item = identifier .

<label-item> must conform to the standard identifier format.

• PMP labels have not to be declared before their use (not a standard Pascal Label declaration).

<label-item> is local to the current procedure, function, main program or unit initialization block, so a GOTO cannot jump outside of the current scope.

Forward label references are allowed in a PMP program.

PMP labels translate to an internal representation as for any identifier (prefixed with module name and procedure or function name).

[Spaghetti code]

FOR I := 1 TO 10 DO
 BEGIN
   … // Do Something
   IF A THEN GOTO Label_A;
   … // Something not executed if A = TRUE
   GOTO Label_B;
   Label_A:
   … // Something executed if A = TRUE
   Label_B:
 END;

• In its current implementation PMP does not check for branch to statements that are in FOR / WHILE / REPEAT loops, so this would make unpredictable results, especially in a FOR loop since the loop variable is not initialized:

[Bad code]

IF A THEN GOTO Label_A;
FOR I := 1 TO 10 DO
 BEGIN
   … // Do Something
   Label_A:
   … // Do Something else
 END;

Well, everybody would say that this is not a good practice (indeed), but PMP will not flag it…