Null object: Difference between revisions
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{{task|Basic language learning}} |
{{task|Basic language learning}} |
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[[Category:Simple]] |
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'''Null''' (or '''nil''') is the computer science concept of an undefined or unbound object. |
'''Null''' (or '''nil''') is the computer science concept of an undefined or unbound object. |
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Some languages have an explicit way to access the null object, and some don't. |
Some languages have an explicit way to access the null object, and some don't. |
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Some languages distinguish the null object from [[undefined values]], and some don't. |
Some languages distinguish the null object from [[undefined values]], and some don't. |
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;Task: |
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Show how to access null in your language by checking to see if an object is equivalent to the null object. |
Show how to access null in your language by checking to see if an object is equivalent to the null object. |
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''This task is not about whether a variable is defined. The task is about "null"-like values in various languages, which may or may not be related to the defined-ness of variables in your language.'' |
''This task is not about whether a variable is defined. The task is about "null"-like values in various languages, which may or may not be related to the defined-ness of variables in your language.'' |
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