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    <p>That doesn't exactly make sense. You'd need two versions of that
      function in all likelihood - one left-biased and another
      right-biased.<br>
    </p>
    <br>
    <div class="moz-cite-prefix">On 07/31/2018 02:07 AM, Marc Busqué
      wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:alpine.LNX.2.21.1807310857500.2536@localhost">Hi!
      <br>
      <br>
      I have two functions:
      <br>
      <br>
      ```
      <br>
      foo :: a -> Maybe b
      <br>
      bar :: a -> Maybe c
      <br>
      ```
      <br>
      <br>
      From which I want to build a higher order function:
      <br>
      <br>
      ```
      <br>
      foobar :: a -> (a -> Maybe b) -> (a -> Maybe c) ->
      Either b c
      <br>
      ```
      <br>
      <br>
      The implementation I need is:
      <br>
      <br>
      ```
      <br>
      foobar x f g =
      <br>
        case (f x) of
      <br>
          Nothing -> g x
      <br>
          Just y  -> Just y
      <br>
      ```
      <br>
      <br>
      I'm a bit surprised that looking at hoogle I don't find a built-in
      <br>
      solution for this quite common need for `Maybe` types (or perhaps
      for
      <br>
      any monad).
      <br>
      <br>
      Am I looking in the wrong way? Does it exist a similar abstraction
      but
      <br>
      with a different shape?
      <br>
      <br>
      Thanks in advance,
      <br>
      <br>
      Marc Busqué
      <br>
      <a class="moz-txt-link-freetext" href="http://waiting-for-dev.github.io/about/">http://waiting-for-dev.github.io/about/</a><br>
      <br>
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      <br>
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    </blockquote>
    <br>
    <div class="moz-signature">-- <br>
      <br>
      <br>
      <br>
      <strong
        style="color:#000;font-family:Helvetica,Arial;font-size:116%;">Vanessa
        McHale</strong><br>
      <span
        style="color:#000;font-family:Helvetica,Arial;font-size:100%;"><span
          style="color:#f00">Functional Compiler Engineer |</span>
        Chicago, IL</span>
      <br>
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