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<div class="moz-cite-prefix">Oke, <br>
<br>
Then I make there a mistake,<br>
<br>
What I try to do is to send the file to parseMessage and let
IsValid check if it´s have the right format. <br>
<br>
Then after the where I try to check if the function isValid
returns true or false. <br>
<br>
Roelof<br>
<br>
<br>
Konstantine Rybnikov schreef op 23-2-2015 om 16:03:<br>
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cite="mid:CAAbahfS0Sq0hGJuis5hzLj5ZTzQALdZrAEq6AevjMUDSsnaa5g@mail.gmail.com"
type="cite">
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<div>Roelof,<br>
<br>
</div>
You defined isValid function in the upper-scope first, and
then you defined a symbol (variable) that re-wrote that name
to something different (string "Geldige string"). That's why
you get an error saying it doesn't expect arguments.<br>
<br>
</div>
My suggestion is to rename second isValid.<br>
<br>
</div>
Good luck.<br>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Mon, Feb 23, 2015 at 4:50 PM, Roelof
Wobben <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:r.wobben@home.nl" target="_blank">r.wobben@home.nl</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div>Chaddaï Fouché schreef op 23-2-2015 om 13:20:<br>
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<div>Note that Roelof is doing the CIS 194 Homework
<a moz-do-not-send="true"
href="http://www.seas.upenn.edu/%7Ecis194/fall14/hw/03-ADTs.pdf"
target="_blank">http://www.seas.upenn.edu/~cis194/fall14/hw/03-ADTs.pdf</a>
(the older version of fall2014, not the one
currently running). This is much clearer than
Roelof's description, and gives among other
information an algebraic datatype to represent log
messages.<br>
<br>
<br>
-- <br>
</div>
Jedaï<br>
</div>
</blockquote>
<br>
</span> Correct and Im trying to do exercise 1 of Week 2,<br>
<br>
I have tried this solution : <br>
<br>
-- | Main entry point to the application.<br>
{-# OPTIONS_GHC -Wall #-}<br>
<br>
module LogAnalysis where<br>
<br>
import Log;<br>
import Data.Char (isLetter, isDigit) <br>
<br>
isValid :: [Char] -> Bool <br>
isValid s = go (words s)<br>
where<br>
go ([a]:b:_) = isLetter a && all isDigit b<br>
go _ = False <br>
<br>
parseMessage :: [Char] -> [Char]<br>
parseMessage s = isValid s <br>
where <br>
isValid = "Geldige string"<br>
_ = "Ongeldige string"<br>
<br>
-- | The main entry point.<br>
main :: IO ()<br>
main = do<br>
putStrLn $ parseMessage "I 4764 He trusts to you to
set them free," <br>
<br>
<br>
but I see this error message : <br>
<br>
<div>src/LogAnalysis.hs@16:18-16:27 </div>
<div><span>Couldn't match expected type ‘[Char] ->
[Char]’ with actual type </span>
<div style="font-size:14px">[<span>Char</span>]</div>
<span> The function </span>
<div style="font-size:14px"><span>isValid</span></div>
<span> is applied to one argument, but its type </span>
<div style="font-size:14px">[<span>Char</span>]</div>
<span> has none</span><span title="Click to show/hide
extra information"> …</span><span
style="display:inline"> In the expression: isValid s
In an equation for ‘parseMessage’: parseMessage s =
isValid s where isValid = "Geldige string" _ =
"Ongeldige string"<br>
<br>
<br>
</span></div>
<br>
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</blockquote>
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<br>
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