Q30858: QuickBASIC 4.x Procedure Name Followed By Colon Not Executed
Article: Q30858 Product(s): See article Version(s): 4.00 4.00b 4.50 Operating System(s): MS-DOS Keyword(s): ENDUSER | buglist4.00 buglist4.00b buglist4.50 b_basiccom | mspl13_basic Last Modified: 20-SEP-1990 When you use the implied CALL syntax, a SUBprogram procedure name followed immediately by a colon is mistaken for a label name. This prevents the SUBprogram from being executed. The problem occurs both inside the QB.EXE environment and when compiled from BC.EXE. Microsoft has confirmed this to be a problem in QuickBASIC versions 4.00, 4.00b, and 4.50 for MS-DOS; in Microsoft BASIC Compiler versions 6.00 and 6.00b (buglist6.00, buglist6.00b) for MS-DOS and MS OS/2; and in Microsoft BASIC Professional Development System (PDS) versions 7.00 and 7.10 for MS-DOS and MS OS/2 (buglist7.00, buglist7.10). We are researching this problem and will post new information here as it becomes available. This is not an issue in QuickBASIC version 3.00 and earlier versions, because these versions require the CALL statement to execute SUBprogram procedures. The implied CALL syntax was added to QuickBASIC version 4.00. An "implied CALL" is where a procedure name is invoked without a preceding "CALL" statement, then followed by parameters passed in a list without surrounding parentheses. The following are two workarounds for this problem: 1. Place the command following the procedure name on a new line so that the colon is not necessary. 2. Use an explicit CALL statement to invoke the procedure. The following code example demonstrates the problem: DECLARE SUB subtest () CLS PRINT "this is the main" subtest: PRINT "the end" SUB subtest PRINT "this is sub test" END SUB The procedure (SUBTEST) above will not be executed because the compiler mistakes the procedure name followed by a colon for a label name. The following code will execute correctly: DECLARE SUB subtest () CLS PRINT "this is the main" call subtest: PRINT "the end" SUB subtest PRINT "this is sub test" END SUB
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