ATTENTION: I've created a new thinCore.dll version for this script.
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I did this because most of thinBasic API interfaces use EXTENDED numeric data type and EXTENDED (10 bytes) are not supported in VB.
Not quite. Microsoft hides it but for backward compatibility to 16 bit they kept the datatype - also its rounded up to use 3x4 bytes in memory but actually it calculates as real10 but is named Longdouble. There are some Api-functions to it (search "LDOUBLE")