private static CaseExpression reduceCaseExpression(WordCollection wc)
{
CaseExpression ret = new CaseExpression();
IdentifierWord id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("IS", Config.SCVariable)))
{
wc.ShiftNext();
ret.CaseType = CaseExpressionType.Is;
OperatorWord opWT = wc.Current as OperatorWord;
if (opWT == null)
{
throw new CodeEE("ISキーワードの後に演算子がありません");
}
OperatorCode op = opWT.Code;
if (!OperatorManager.IsBinary(op))
{
throw new CodeEE("ISキーワードの後の演算子が2項演算子ではありません");
}
wc.ShiftNext();
ret.Operator = op;
ret.LeftTerm = reduceTerm(wc, false, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.LeftTerm == null)
{
throw new CodeEE("ISキーワードの後に式がありません");
}
Type type = ret.LeftTerm.GetOperandType();
return(ret);
}
ret.LeftTerm = reduceTerm(wc, true, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.LeftTerm == null)
{
throw new CodeEE("CASEの引数は省略できません");
}
id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("TO", Config.SCVariable)))
{
ret.CaseType = CaseExpressionType.To;
wc.ShiftNext();
ret.RightTerm = reduceTerm(wc, true, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.RightTerm == null)
{
throw new CodeEE("TOキーワードの後に式がありません");
}
id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("TO", Config.SCVariable)))
{
throw new CodeEE("TOキーワードが2度使われています");
}
if (ret.LeftTerm.GetOperandType() != ret.RightTerm.GetOperandType())
{
throw new CodeEE("TOキーワードの前後の型が一致していません");
}
return(ret);
}
ret.CaseType = CaseExpressionType.Normal;
return(ret);
}
/// <summary>
/// カンマで区切られたCASEの引数を一括して取得。行端で終わる。
/// </summary>
/// <param name="st"></param>
/// <returns></returns>
public static CaseExpression[] ReduceCaseExpressions(WordCollection wc)
{
List <CaseExpression> terms = new List <CaseExpression>();
while (!wc.EOL)
{
terms.Add(reduceCaseExpression(wc));
wc.ShiftNext();
}
CaseExpression[] ret = new CaseExpression[terms.Count];
terms.CopyTo(ret);
return(ret);
}
private static CaseExpression reduceCaseExpression(WordCollection wc)
{
CaseExpression ret = new CaseExpression();
IdentifierWord id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("IS", Config.SCVariable)))
{
wc.ShiftNext();
ret.CaseType = CaseExpressionType.Is;
OperatorWord opWT = wc.Current as OperatorWord;
if (opWT == null)
throw new CodeEE("ISキーワードの後に演算子がありません");
OperatorCode op = opWT.Code;
if (!OperatorManager.IsBinary(op))
throw new CodeEE("ISキーワードの後の演算子が2項演算子ではありません");
wc.ShiftNext();
ret.Operator = op;
ret.LeftTerm = reduceTerm(wc, false, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.LeftTerm == null)
throw new CodeEE("ISキーワードの後に式がありません");
Type type = ret.LeftTerm.GetOperandType();
return ret;
}
ret.LeftTerm = reduceTerm(wc, true, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.LeftTerm == null)
throw new CodeEE("CASEの引数は省略できません");
id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("TO", Config.SCVariable)))
{
ret.CaseType = CaseExpressionType.To;
wc.ShiftNext();
ret.RightTerm = reduceTerm(wc, true, TermEndWith.Comma, VariableCode.__NULL__);
if (ret.RightTerm == null)
throw new CodeEE("TOキーワードの後に式がありません");
id = wc.Current as IdentifierWord;
if ((id != null) && (id.Code.Equals("TO", Config.SCVariable)))
throw new CodeEE("TOキーワードが2度使われています");
if (ret.LeftTerm.GetOperandType() != ret.RightTerm.GetOperandType())
throw new CodeEE("TOキーワードの前後の型が一致していません");
return ret;
}
ret.CaseType = CaseExpressionType.Normal;
return ret;
}
public CaseArgument(CaseExpression[] args)
{
CaseExps = args;
}
/// <summary>
/// カンマで区切られたCASEの引数を一括して取得。行端で終わる。
/// </summary>
/// <param name="st"></param>
/// <returns></returns>
public static CaseExpression[] ReduceCaseExpressions(WordCollection wc)
{
List<CaseExpression> terms = new List<CaseExpression>();
while (!wc.EOL)
{
terms.Add(reduceCaseExpression(wc));
wc.ShiftNext();
}
CaseExpression[] ret = new CaseExpression[terms.Count];
terms.CopyTo(ret);
return ret;
}