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<title>Language Reference - Variables</title>
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<body><br>
&nbsp;<span class="Command">&nbsp;Variables&nbsp;</span><br>
<blockquote> 
  <p>Variables may be of any basic data type, or a custom type. A variable's type 
    is determined by a special character that follows its identifier.<br>
    <br>
    <span class="header"> Variable Types</span></p>
  <blockquote>
    <p>These special characters are called 'type tags' and are: </p>
  </blockquote>
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        <blockquote><br>
          <p> % = For integer variables </p>
          <p> # = For floating point variables </p>
          <p> $ = For string variables </p>
          <p> .{typename} For custom type variables</p>
        </blockquote>
      
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<blockquote> 
  <blockquote>
    <p> Here are some examples of valid variables: </p>
  </blockquote>
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  >
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      <p><br>
      </p>
      <blockquote>
        <p>Score%</p>
        <p>Lives% </p>
        <p>x_speed# </p>
        <p>y_speed# </p>
        <p>name$ </p>
        <p>title$ </p>
        <p>ali.Alien </p>
        <p>player.Player</p>
      </blockquote>
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<blockquote> 
  <blockquote>
    <p>The type tag only needs to be added the first time you use a variable, 
      after that you can leave the type tag off if you wish. <br>
      <br>
      If you don't supply a type tag the first time a variable is used, the variable 
      defaults to an integer. <br>
    </p>
    <p>It is illegal to use the same variable name with a different type. For 
      example, if you already have an integer variable called 'name%', it is illegal 
      to also have a string variable called 'name$' <br>
    </p>
  </blockquote>
  <p class="header">Setting Variables</p>
  <blockquote> 
    <p>The '=' keyword is used to assign a value to a variable. For example: </p>
    <blockquote> 
      <p><i>score%=0 </i></p>
    </blockquote>
    <p> ... assigns the value '0' to the integer variable 'score'.</p>
  </blockquote>
  <p><span class="header">Variable Scope</span><br>
  </p>
  <blockquote> 
    <p>Variables may also be either '<b>global</b>', or '<b>local</b>'. This refers 
      to where in a program a variable may be used.</p>
    <blockquote> 
      <p>- <b>Global variables</b> can be used from anywhere in the program. <br>
        <br>
        - <b>Local variables</b> can only be used within the function they are 
        created in. </p>
    </blockquote>
    <p> The '<b>Global</b>' keyword is used to define one or more global variables. 
      For example: </p>
    <blockquote> 
      <p><i>Global Score=0,Lives=3,Player_up=1 </i></p>
    </blockquote>
    <p> ... defines 3 global variables. </p>
    <p> Similarly, '<b>Local</b>' is used to define local variables: </p>
    <blockquote> 
      <p><i>Local temp_x=x,temp_y=y </i></p>
    </blockquote>
    <p>If you use a variable without defining it as either local or global, it 
      defaults to being local. </p>
  </blockquote>
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