Tech Tip: Different behaviors of "@" character depending on the side of a comparison
PRODUCT: 4D | VERSION: 17 | PLATFORM: Mac & Win
Published On: January 3, 2019
When making a string comparison with the @ wildcard, the common convention is to use the wildcard string on the right side of the comparison. The reason for this convention is that the "@" character is only treated as a wildcard on the right side and a literal character on the left side. Take for example a string comparison between "abc" and "a@c" used in alternating sides.
C_BOOLEAN($yResult1;$yResult2) $yResult1:=("abc"="a@c") $yResult2:=("a@c"="abc") |
For the first result,"a@c" is treated as the wildcard string where the wildcard will take effect and the boolean evaluates to True. For the second result, "a@c" is treated as a literal string where the wildcard is completely ignored and the boolean evaluates to False.
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In short, always be sure to use any strings with wildcards on the right side of the comparison in order for the "@" character to take effect.