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<try>
  <call method="Open" class="System.File"/>
  <catch exception="System.FileNotFoundException">
    <call method="Show" class="System.Dialog">
      <parameter value="The file could not be found..."/>
    </call>
  </catch>
</try>

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<call method="<method>" class="<class>">
      <parameter value="<param1>"/>
      <parameter value="<param2>"/>
    </call>

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call <class> <method> <param1> <param2> .

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try
  call "System.File" "Open" .
.
catch "System.FileNotFoundException"
  call "System.Dialog" "Show"
  "The file could not be found...".
.

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parse_statement_block(xmlnode) {
  stmtblock = new StatementBlock();
  foreach(child in xmlnode.children)
    stmtblock.push(parse_statement(child));
  return stmtblock;
}

parse_statement(xmlnode) {
  switch(xmlnode.getTagName()) {
    case "try": return parse_try_block(xmlnode);
    case "return": return parse_return(xmlnode);
    case "if": return parse_if(xmlnode);
    // other statements here
    default: error ("Unknown tag");
  }
}

parse_if(xmlnode) {
   ifstmt = new If();
   ifstmt.condition = null;
   ifstmt.then = null;
   ifstmt.else = null;

   foreach(xmlchild in xmlnode.children) {
      switch(xmlchild.getTagName()) {
        case "condition":
          if(ifstmt.condition != null) error("<if> has multiple <condition> clauses.");
          ifstmt.condition = parse_expression(xmlchild);
        case "then":
          if(ifstmt.then != null) error("<if> has multiple <then> clauses.");
          ifstmt.then = parse_block(xmlchild);
        case "else":
          if(ifstmt.else != null) error("<if> has multiple <else> clauses.");
          ifstmt.else = parse_block(xmlchild);
        break;
      }
   }

   if(ifstmt.condition == null) error("<if> requires a <condition> clause.");
   if(ifstmt.then == null) error ("<if> requires a <then> clause.");
   return ifstmt;
};

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parse_statement_block(lexer) {
  if(lexer.peek() == "{")
    // must be a block
    stmtblock = new StatementBlock();
    lexer.mustbe("{");
    while(lexer.peek() != "}")
      stmtblock.push(parse-statement);
    lexer.mustbe("}");
    return stmtblock;
  }
  else // just a single statement
    return parse_statement(lexer);
}

parse_statement(lexer) {
  switch(lexer.token()) {
    case "try": return parse_try_block(lexer);
    case "return": return parse_return(lexer);
    case "if": return parse_if(lexer);
    // other statements here
    default: return parse_expression(lexer);
  }
}

parse_if(lexer) {
  ifstmt = new If();

  lexer.mustbe("(");
  ifstmt.condition = parse_expression(lexer);
  lexer.mustbe(")");
   
  ifstmt.true = parse_statement_block(lexer);
  if(lexer.peek() == "else") {
    lexer.mustbe("else");
    ifstmt.false = parse_statement_block(lexer);
  } else
    ifstmt.false = null;

  return ifstmt;
};

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child: statement | literal
statement: "(" literal { child } ")"

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<call>

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<call function="your function name" class="the class the function belongs to">
   <parameter>first parameter</parameter>
   <parameter>second parameter</parameter>
</call>

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<call function="" class="System.IO">

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<declare_variable>
<name>X</name>
<type>float</name>
<initial_value>
  <float_literal>10.0</float_literal>
</initial_value>
</declare_variable>

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<if>
  <condition>
    <equal>
       <float_literal>10.0</float_literal>
       <variable>..

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<cls:class name="System" static="true">
  <cls:method name="GetDate" type="Date" static="true">
    <!--Get Month-->
    <clk:GetMonth/>  <!--Returns the month value from the Real Time Clock.  Output: AL=Month-->

    <cpu:CopyRegisterToOperand8/>
    <op:AL-DHRegister/>

    <!--Get Day-->
    <clk:GetDayOfMonth/>  <!--Returns the day of the month value from the Real Time Clock.  Output: AL=DayOfMonth-->

    <cpu:CopyRegisterToOperand8/>
    <op:AL-DLRegister/>

    <!--Get Year-->
    <clk:GetYear/>  <!--Returns the year value from the Real Time Clock.  Output: AL=Year-->

    <cpu:CopyRegisterToOperand8/>
    <op:AL-CLRegister/>

    <!--Get Century-->
    <clk:GetCentury/>  <!--Returns the century value from the Real Time Clock.  Output: AL=Century-->

    <cpu:CopyRegisterToOperand8/>
    <op:AL-CHRegister/>

    <date:CreateObject/>  <!--Creates a new Date object.  Input: CX=Year DH=Month DL=Day  Output: DI=Object-->

    <cpu:ReturnToNearCaller/>
  </cls:method>