Fuzion • Idioms • Idiom # 41: Reverse a string

Idiom # 41: Reverse a string

Code

There is no feature in Fuzion's strings to reverse the characters, so we have to do it manually: First, the string that is usually represented as utf8 is converted to an array of codepoints. This array is then reversed and folded back into a string using string's concat monoid.

t := s
  .codepoints_array
  .reverse
  .as_Strings
  .fold String.concat

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t := s
  .codepoints_array
  .reverse
  .as_Strings
  .fold String.concat
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Running Example

s := "café"
t := s
  .as_codepoints
  .as_array
  .reverse
  .as_strings
  .fold String.concat
say "$s -> $t"

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s := "café"
t := s
  .as_codepoints
  .as_array
  .reverse
  .as_strings
  .fold String.concat
say "$s -> $t"
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Since this example reverse the codepoints and not bytes or utf16 chars, this also works for unicode chars outside the basic plane:

s := "👋🌍❗"
t := s
  .as_codepoints
  .as_array
  .reverse
  .map String c->c
  .fold String.concat
say "$s -> $t"

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s := "👋🌍❗"
t := s
  .as_codepoints
  .as_array
  .reverse
  .map String c->c
  .fold String.concat
say "$s -> $t"
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

last changed: 2024-07-01

next: Idiom # 42: Continue outer loop