Tag: boolean

The Varying (and Variant) Value of True

[Estimated Reading Time: < 1 minutes] My most recent posts have prompted a bit of discussion, and it seems some concern, regarding the implementation of Boolean values in Delphi. The concern at least I think is unwarranted, as long as you avoid explicitly comparing a Boolean value to the True constant and allow the compiler to logically evaluate the Boolean itself. But in the follow up investigations of one commenter (thank you Arthur), a further occurrence of the alternate -1 identity of True has been identified: Variants.

(True = 1) and (True = ‘-1’) ?

[Estimated Reading Time: 4 minutes] It has been observed that the Delphi documentation states that the constants True and False have the values 1 and 0 respectively, not the -1 and 0 that the default string conversions apply. This does actually make sense but also lays a trap for the unwary.

M	T	W	T	F	S	S
						1
2	3	4	5	6	7	8
9	10	11	12	13	14	15
16	17	18	19	20	21	22
23	24	25	26	27	28	29
30	31