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Hello, <br>
<br>
To practice recursion I try to make some functions of Data list
myself on the recursive way.<br>
<br>
First I will try last.<br>
<br>
So I did this : <br>
<br>
-- | Main entry point to the application.<br>
module Main where<br>
<br>
-- | The main entry point.<br>
last' :: [a] -> a <br>
last' [] = [] <br>
last' (x:xs) = last xs<br>
<br>
<br>
but now I see this error message : <br>
<br>
<div class="ide-error-span">src/Main.hs@6:12-6:14 </div>
<div class="ide-error-msg"><span>Couldn't match expected type </span>
<div class="CodeMirror cm-s-default" style="font-size: 14px;"><span
class="cm-variable">a</span></div>
<span> with actual type </span>
<div class="CodeMirror cm-s-default" style="font-size: 14px;">[<span
class="cm-variable">t0</span>]</div>
<span> </span>
<div class="CodeMirror cm-s-default" style="font-size: 14px;"><span
class="cm-variable">a</span></div>
<span> is a rigid type variable bound by the type signature for
last' :: [a] -> a at
/home/app/isolation-runner-work/projects/112712/session.207/src/src/Main.hs:5:10
Relevant
bindings include last' :: [a] -> a (bound at
/home/app/isolation-runner-work/projects/112712/session.207/src/src/Main.hs:6:1)</span><span
title="Click to show/hide extra information"
class="ide-error-collapse-btn"> …<br>
<br>
I my oponion I have said that the input is a array and the
output a string, <br>
<br>
Roelof<br>
<br>
</span></div>
<br>
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