Undefined values: Difference between revisions
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Puppydrum64 (talk | contribs) m (→{{header|6502 Assembly}}: Rephrased for clarity) |
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=={{header|6502 Assembly}}== |
=={{header|6502 Assembly}}== |
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Every operation will return some 8-bit value, so there is no <code>null</code> in 6502 or anything like that. However, it is possible for certain actions to have '''undefined behavior''', for example, attempting to read from a write-only memory-mapped port might return any value from 0-255, depending on what was last on the data bus. |
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Undefined values don't exist per se, but reading from write-only memory-mapped ports can result in undefined behavior, namely, the contents of the read can be whatever was on the data bus last. |
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=={{header|ActionScript}}== |
=={{header|ActionScript}}== |
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ActionScript has a special '''undefined''' value which applies to untyped variables and properties of dynamic classes which have not been initialized. |
ActionScript has a special '''undefined''' value which applies to untyped variables and properties of dynamic classes which have not been initialized. |
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