Conditional (computer programming)
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Pattern matching is not strictly speaking always a choice construct, because it is possible in Haskell to write only one alternative, which is guaranteed to always be matched – in this situation, it is not being used as a choice construct, but simply as a way to bind names to values. However, it is frequently used as a choice construct in the languages in which it is available.
Hash-based conditionals
In programming languages that have associative arrays or comparable data structures, such as Python, Perl, PHP or Objective-C, it is idiomatic to use them to implement conditional assignment.cite-ref-13[13]
pet = input("Enter the type of pet you want to name: ")
known_pets = {
"Dog": "Fido",
"Cat": "Meowsles",
"Bird": "Tweety",
}
my_name = known_pets[pet]
In languages that have anonymous functions or that allow a programmer to assign a named function to a variable reference, conditional flow can be implemented by using a hash as a dispatch table.
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