| QTIPS - Using @Upper.Case and @Lower.Case with Foreign Languages |
| @ATTACK - @Lower.Case |
| @ATTACK - @Upper.Case |
| Sorting out Collation Sequences by Mike Pope |
| File Variables |
| Argument passing - Subroutines and Functions - Mike Pope |
| RevTech Replies - Mike Pope (RevTech UK Ltd) |
| Symbol Table Structure |
| QTIPS - Btree.Extract |
| Comp |
| Reader's Clinic - Removing "Searching Cross References" Message |
| @ATTACK - @List.Active |
| IConvs / OConvs |
| Reader's Clinic - Stop Lists |
| REVMEDIA Revisited |
| REVMEDIA Revisited |
| Argument passing - Subroutines and Functions - Mike Pope |
| Caching in on the Frames Array - Mike Pope |
| QTIPS - Fast Dynamic Array Building |
| RTP Series - RTP25 |
| RTP Series - RTP27 |
| QTIPS - Printing Large Variables from the Debugger |
| VERBatim - V87 |
| @ATTACK - @TCL.Stack |
RevMedia FKB
| Document | V3I10A1 |
| Title | QTIPS - Testing For Boolean False |
| Keywords | BOOLEAN FALSE LEN |
| Text | It is frequently the case that simple Boolean logic is used to detect whether a variable contains a value e g IF X THEN However this has the disadvantage that if the variable ever contains 0 and 0 is a valid response then the Boolean test would fail This is of particular significance when processing keys unknown data etc To get around this it has become traditional to test USING Len() i e IF LEN(X) THEN Whilst this approach is twice as slow you are unlikely to notice the difference between 0 00005 and 0 0001 of a second unless you are processing hundreds of thousands of records However this approach should only be used when the end result is not going to be used to extract FROM a dynamic array This is because a Len() will return true for a 0 and will thus result in an ARRAY<0> being used As an EXAMPLE of this use F2 at TCL to get the TCL Popup and enter 0 the entire TCL stack returns to the TCL window WITH interesting results! (Volume 3 Issue 10 Page 4) |
Page last modified: 08/02/03