Fuzion • Idioms • Idiom # 225: Declare and use an optional argument

Idiom # 225: Declare and use an optional argument

Code

f(T type, x option T) =>
  x ? t T => say "x is present $t"
    | nil => say "x is not present"

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f(T type, x option T) =>
  x ? t T => say "x is present $t"
    | nil => say "x is not present"
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Running Example

ex225 is

  f(T type, x option T) =>
    x ? t T => say "x is present $t"
      | nil => say "x is not present"

  f 42
  f "some text"
  f String nil

  # the following does not work yet, see https://github.com/tokiwa-software/fuzion/issues/121
  # f nil
  # f nil nil

  f -1⁄12
  f "Die Würde des Menschen ist unantastbar.".split

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ex225 is
  f(T type, x option T) =>
    x ? t T => say "x is present $t"
      | nil => say "x is not present"
  f 42
  f "some text"
  f String nil
  # the following does not work yet, see https://github.com/tokiwa-software/fuzion/issues/121
  # f nil
  # f nil nil
  f -1⁄12
  f "Die Würde des Menschen ist unantastbar.".split
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

last changed: 2024-07-01

next: Idiom # 226: Delete last element from list