code: private Expr parseNegationExpression(EnclosingScope scope, boolean terminated) {
  		int start = index;
  		match(Minus);
  		Expr e = parseAccessExpression(scope, terminated);
  		return annotateSourceLocation(new Expr.IntegerNegation(Type.Void, e), start);
  	}
docs: Parse a negation expression, which is of the form:
  
  <pre>
  TermExpr::= ...
  |  '-' Expr
  </pre>
  
  @param scope
  The enclosing scope for this statement, which determines the
  set of visible (i.e. declared) variables and also the current
  indentation level.
  @param terminated
  This indicates that the expression is known to be terminated
  (or not). An expression that's known to be terminated is one
  which is guaranteed to be followed by something. This is
  important because it means that we can ignore any newline
  characters encountered in parsing this expression, and that
  we'll never overrun the end of the expression (i.e. because
  there's guaranteed to be something which terminates this
  expression). A classic situation where terminated is true is
  when parsing an expression surrounded in braces. In such case,
  we know the right-brace will always terminate this expression.
  
  @return