because if you don't have a BEGIN { } block around the require, the constants will be loaded at runtime. In other words, they aren't yet known at compile time of the script. Adding parens in this case is a hint to the compiler that the constants are subroutines (which they internally are), not barewords.

In reply to Re^3: How to import constants from another perl script by Anonymous Monk
in thread How to import constants from another perl script by stevenswj

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