private void SerializeSlice(List<string> output, SliceExpression slice)
{
SerializeExpression(output, slice.Root);
output.Add("[");
for (int i = 0; i < slice.Components.Length; ++i)
{
if (i > 0) output.Add(":");
if (slice.Components[i] != null)
{
SerializeExpression(output, slice.Components[i]);
}
}
output.Add("]");
}
private static Expression ParseEntityWithSuffix(TokenStream tokens)
{
Expression expression = ParseRootEntity(tokens);
bool nextAllowed;
bool keepGoing = true;
string next = tokens.PeekValue();
while (keepGoing)
{
switch (next)
{
case "[":
// indexing or slicing
Token bracketToken = tokens.Pop();
List<Expression> sliceComponents = new List<Expression>();
nextAllowed = true;
while (!tokens.PopIfPresent("]"))
{
if (!nextAllowed) tokens.PopExpected("]"); // throws
if (tokens.IsNext(":"))
{
sliceComponents.Add(null);
}
else
{
sliceComponents.Add(Parse(tokens));
}
nextAllowed = tokens.PopIfPresent(":");
}
if (nextAllowed)
{
sliceComponents.Add(null);
}
if (sliceComponents.Count == 0)
{
throw new ParserException(bracketToken, "Unexpected token.");
}
else if (sliceComponents.Count == 1)
{
expression = new IndexExpression(expression, bracketToken, sliceComponents[0]);
}
else if (sliceComponents.Count <= 3)
{
expression = new SliceExpression(expression, bracketToken, sliceComponents);
}
else
{
throw new ParserException(bracketToken, "Slice expression has too many components.");
}
break;
case "(":
// function call
Token openParen = tokens.Pop();
nextAllowed = true;
List<Expression> args = new List<Expression>();
while (!tokens.PopIfPresent(")"))
{
if (!nextAllowed) tokens.PopExpected(")"); // throws
args.Add(Parse(tokens));
nextAllowed = tokens.PopIfPresent(",");
}
expression = new FunctionInvocation(expression, args);
break;
case ".":
// dot field
Token dotToken = tokens.Pop();
Token fieldToken = tokens.Pop();
if (!Util.IsIdentifier(fieldToken))
{
throw new ParserException(fieldToken, "Invalid field.");
}
expression = new DotField(expression, dotToken, fieldToken, fieldToken.Value);
break;
default:
keepGoing = false;
break;
}
next = tokens.PeekValue();
}
return expression;
}
