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    <div class="moz-cite-prefix">Oke, I read that part. <br>
      <br>
      Then I would be age p = ag <br>
      <br>
      Roelof<br>
      <br>
      <br>
      <br>
      Sumit Sahrawat, Maths & Computing, IIT (BHU) schreef op
      19-2-2015 om 18:03:<br>
    </div>
    <blockquote
cite="mid:CAJbEW8MU+66EC2H8ChBZER1atx0r4TL0aOAsJmbwMvJjhjMzBw@mail.gmail.com"
      type="cite">
      <div dir="ltr"><font face="monospace, monospace">When you use
          record syntax, accessors are automatically created for you.
          So,</font>
        <div><font face="monospace, monospace"><br>
          </font></div>
        <div><font face="monospace, monospace">data Person = Person {<br>
          </font></div>
        <div><font face="monospace, monospace">      name     :: String</font></div>
        <div><font face="monospace, monospace">    , age      :: Integer</font></div>
        <div><font face="monospace, monospace">    , favThing :: String</font></div>
        <div><font face="monospace, monospace">    }</font></div>
        <div><font face="monospace, monospace"><br>
          </font></div>
        <font face="monospace, monospace">means that name, age and
          favThing are functions that do exactly what you want:</font>
        <div><font face="monospace, monospace"><br>
          </font>
          <div><font face="monospace, monospace">    name     :: Person
              -> String</font></div>
          <div><font face="monospace, monospace">    age      :: Person
              -> Integer</font></div>
          <div><font face="monospace, monospace">    favThing :: Person
              -> String</font></div>
          <div><font face="monospace, monospace"><br>
            </font></div>
          <div><font face="monospace, monospace">So you just need to
              call age on a Person value to get the age.</font></div>
          <div><font face="monospace, monospace">Due to this
              functionality, the names in record syntax can not start
              with an uppercase letter.</font></div>
        </div>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On 19 February 2015 at 22:27, 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">
            <div bgcolor="#FFFFFF" text="#000000">
              <div>Thanks, <br>
                <br>
                That is not what I mean , <br>
                <br>
                I mean this : <br>
                <span class=""> <br>
                  <span>data</span> Person <span>=</span> Person<br>
                        <span>{</span> name <span>::</span> <span>String</span>
                  ,<br>
                </span>         Age <span>::</span> Integer<span></span>
                , <br>
                        FavThing <span>::</span> <span>String</span> <span></span>
                <span>}</span> <br>
                <br>
                <br>
                and i want to get the Age I could do this : <br>
                <br>
                getAge <span>(Person</span> <span>{age</span> <span>=</span>
                ag})<span></span> <span>=</span> ag<br>
                <br>
                Roelof<br>
                <br>
                <span></span> <br>
                Sumit Sahrawat, Maths & Computing, IIT (BHU) schreef
                op 19-2-2015 om 17:37:<br>
              </div>
              <div>
                <div class="h5">
                  <blockquote type="cite">
                    <div dir="ltr">
                      <div>I can't understand what you mean by those
                        colons in the second definition of Person. If
                        you're thinking of type signatures, then that
                        doesn't work in haskell.</div>
                      <div>In an ADT, you give names to possible values.
                        So "Name String" will work whereas "Name :
                        String" won't work.</div>
                      <div><br>
                      </div>
                      <div><font face="monospace, monospace">data Person
                          = Name String</font></div>
                      <div><font face="monospace, monospace">           
                          | Age Integer</font></div>
                      <div><font face="monospace, monospace">           
                          | FavThing String</font></div>
                      <div><font face="monospace, monospace"><br>
                        </font></div>
                      means that Person can be <b><i>one of</i></b>
                      these things (which is not what you want).
                      <div><br>
                      </div>
                      <div>What you want is possible with record syntax.
                        He'll detail it later I think.</div>
                      <div>If you're interested in learning about it
                        beforehand, look it up in the haskell wikibook
                        (another great haskell resource).</div>
                      <div><br>
                      </div>
                      <div>More about ADTs in general:    <a
                          moz-do-not-send="true"
href="http://en.wikibooks.org/wiki/Haskell/Type_declarations#data_and_constructor_functions"
                          target="_blank">http://en.wikibooks.org/wiki/Haskell/Type_declarations#data_and_constructor_functions</a></div>
                      <div>The link to the specific section: <a
                          moz-do-not-send="true"
href="http://en.wikibooks.org/wiki/Haskell/More_on_datatypes#Named_Fields_.28Record_Syntax.29"
                          target="_blank">http://en.wikibooks.org/wiki/Haskell/More_on_datatypes#Named_Fields_.28Record_Syntax.29</a></div>
                    </div>
                    <div class="gmail_extra"><br>
                      <div class="gmail_quote">On 19 February 2015 at
                        21:58, 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">
                          <div bgcolor="#FFFFFF" text="#000000"> Hello,
                            <br>
                            <br>
                            Im reading chapter 2 of the CIS 194 course
                            about enumaratuin.<br>
                            <br>
                            Now they give this example : <br>
                            <br>
                            <pre><code><span>-- Store a person's name, age, and favourite Thing.</span>
<span>data</span> <span>Person</span> <span>=</span> <span>Person</span> <span>String</span> <span>Int</span> <span>Thing</span>
  <span>deriving</span> <span>Show</span>

<span>brent ::</span> <span>Person</span>
brent <span>=</span> <span>Person</span> <span>"Brent"</span> <span>31</span> <span>SealingWax</span>

<span>stan ::</span> <span>Person</span>
stan  <span>=</span> <span>Person</span> <span>"Stan"</span> <span>94</span> <span>Cabbage</span>

<span>getAge ::</span> <span>Person</span> <span>-></span> <span>Int</span>
getAge (<span>Person</span> _ a _) <span>=</span> a

I understand how this works. 

But I wonder if there is no "better" way to get the Age. 

Is it now wise to make  a person data like this : 

data Person = Name : String 
    | Age : Integer 
    | FavThing : String 

And if so , how can I get the age then ?

Roelof


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                                <div>Regards</div>
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                                  <div>Sumit Sahrawat</div>
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        -- <br>
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            <div>
              <div dir="ltr">
                <div dir="ltr">
                  <div>Regards</div>
                  <div dir="ltr">
                    <div><br>
                    </div>
                    <div>Sumit Sahrawat</div>
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