<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div dir="ltr"></div><div dir="ltr">Can you do:</div><div dir="ltr"><br></div><div dir="ltr"> (f, g) = let f’ = … in (f’, g’)</div><div dir="ltr"><br></div><div dir="ltr">or is a pattern match not allowed at top level?</div><div dir="ltr"><br></div><div dir="ltr">Jeff</div><div dir="ltr"><br><blockquote type="cite">On Nov 22, 2023, at 4:40 PM, Todd Wilson <twilson@csufresno.edu> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><div dir="ltr">Hello, Cafe:<div><br></div><div>Is there a preferred way to define two top-level mutually recursive functions, f and g, that both use a common local function h such that h is (1) only defined once and (2) does not escape the scope of f and g? I suppose it could be done like this:</div><div><br></div><div><blockquote style="margin:0 0 0 40px;border:none;padding:0px"><font face="monospace">fg = let f ... = ... f,g,h ...<br> g ... = ... f,g,h ...<br> h ... = ... h ...<br> in (f,g)<br></font><font face="monospace">f = fst fg<br>g = snd fg<br></font> </blockquote>but is there something more elegant than this that I'm not seeing?<br></div><div><br></div><div>Todd Wilson</div></div>
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