Gotchas: Difference between revisions
→{{header|Z80 Assembly}}
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System.print(rect.diagonal) // runtime error (if previous line commented out)
// Rectangle does not implement 'sqrt(_)'</lang>
=={{header|Z80 Assembly}}==
===JP (HL)===
This is a bit of misleading syntax. For every other instruction, parentheses indicate a dereference of a pointer.
<lang Z80>
LD HL,(&C000) ;load the word at address &C000 into HL
LD A,(HL) ;treating the value in HL as a memory address, load the byte at that address into A.
EX (SP),HL ;exchange HL with the top two bytes of the stack.
JP (HL) ;set the program counter equal to HL. Nothing is loaded from memory pointed to by HL.</lang>
Strangely enough, [[8080 Assembly]] uses a more sensible <code>PCHL</code> (set Program Counter equal to HL) to describe this function. So this gotcha is actually exclusive to Z80.
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