Class instance pointer added to write procedures

Constant string indexing bug fixed

Functions now allowed in constant expressions

Character array initializer bug fixed

PROGRAM header is now optional

Constant Boolean expression bug fixed

Stack top moving optimized

Strings can be assigned to PChar (C interop)

Formatted output for reals improved

$UNITPATH directive added

Return of Doubles optimized

Loading of Doubles optimized

Assignment of Doubles optimized

FloatToStr bug fixed

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