Operator precedence: Difference between revisions
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=={{header|8th}}== |
=={{header|8th}}== |
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In 8th it's very simple: the currently invoked word has precedence, and items are operated upon in the order they are popped off the stack. |
In 8th it's very simple: the currently invoked word has precedence, and items are operated upon in the order they are popped off the stack. |
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=={{header|6502 Assembly}}== |
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There are two types of indirect addressing: Indirect X and Indirect Y. These differ in that the indirect X mode applies the offset before looking up the address. |
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<lang 6502asm>LDX #$02 |
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LDY #$03 |
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LDA ($20,x) ;uses the values stored at $20+x and $21+x as a memory address, and reads the byte at that address. |
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LDA ($20),y ;uses the values store at $20 and $21 as a memory address, and reads the byte at that address + Y.</lang> |
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The use of parentheses for these modes is required, and nicely illustrates the order of operations. To put it in terms of a hierarchy: |
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<pre> |
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Highest: Indirection: () |
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Middle: Offsetting: ,x ,y |
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Lowest: Reading at the specified address. |
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</pre> |
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=={{header|Ada}}== |
=={{header|Ada}}== |
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