public static ImportExpression Parse(ExpressionWalker ew)
{
ew.IsCurrentOrThrow(ExpressionToken.Import);
ew.NextOrThrow();
// ReSharper disable once UseObjectOrCollectionInitializer
var ret = new ImportExpression();
if (ew.IsCurrent(ExpressionToken.StringLiteral))
{
ret._matchType = new RegexResult[] { ew.Current.Match.AsResult() };
ret.Type = ew.Current.Match.Value.Trim('\"');
}
else
{
ret._matchType = ew.TakeForwardWhile(t => t.Token == ExpressionToken.Period || t.Token == ExpressionToken.Literal)
.Select(t => t.Match.AsResult()).ToArray();
ret.Type = ret._matchType.Select(m => m.Value).StringJoin();
if (ew.IsCurrent(ExpressionToken.As))
{
ret._matchAlias = ew.Next(ExpressionToken.Literal, true).Match.AsResult();
ret.As = ret._matchAlias.Value;
}
}
ew.Next();
return(ret);
}
public static GroupExpression Parse(ExpressionWalker ew, ExpressionToken left, ExpressionToken right)
{
ew.IsCurrentOrThrow(left);
ew.NextOrThrow();
if (ew.Current.Token == right)
{
throw new UnexpectedTokenException($"Expected an expression, found end of group of type {right}");
}
var expr = ParseExpression(ew, typeof(GroupExpression));
var grp = new GroupExpression()
{
_matchLeft = AttributeExtensions.GetAttribute <ExpressionTokenAttribute>(left).Emit.AsResult(), _matchRight = AttributeExtensions.GetAttribute <ExpressionTokenAttribute>(right).Emit.AsResult()
};
if (ew.IsCurrent(ExpressionToken.Or))
{
grp.InnerExpression = TernaryExpression.Parse(ew, expr);
}
else
{
grp.InnerExpression = expr;
}
ew.IsCurrentOrThrow(right);
ew.Next();
return(grp);
}
public static TemplateExpression Parse(ExpressionWalker ew)
{
ew.IsCurrentOrThrow(ExpressionToken.Template);
ew.NextOrThrow();
// ReSharper disable once UseObjectOrCollectionInitializer
var ret = new TemplateExpression();
ew.IsCurrentOrThrow(ExpressionToken.StringLiteral);
ret._matchPath = new RegexResult[] { ew.Current.Match.AsResult() };
ret.Path = ew.Current.Match.Value.StartsWith("\"") ? ew.Current.Match.Value.Substring(1, ew.Current.Match.Length - 2) : ew.Current.Match.Value;
ret._matchForEvery = ew.Next(ExpressionToken.ForEvery, true).Match.AsResult();
ew.NextOrThrow();
ret.Arguments = ArgumentsExpression.Parse(ew, token => token.Token == ExpressionToken.NewLine || token.Token == ExpressionToken.Mod, false, typeof(ForeachExpression));
//we have to fall back because ArgumentsExpression.Parse swallows mod.
ew.IsBack(ExpressionToken.Mod, true);
if (ew.IsCurrent(ExpressionToken.Mod))
{
ew.Back(1);
}
return(ret);
}
public static Expression TryParse(ExpressionWalker ew, Type caller = null)
{
if (ew.IsCurrent(ExpressionToken.Hashtag) && ew.HasNext && ew.IsNext(ExpressionToken.NumberLiteral))
{
return(Parse(ew, caller));
}
return(null);
}
public static ArgumentsExpression Parse(ExpressionWalker ew, ExpressionToken left, ExpressionToken right, bool argsOptional, Type caller = null)
{
var args = new ArgumentsExpression();
ew.IsCurrentOrThrow(left);
ew.NextOrThrow();
var exprs = new List <Expression>();
while (ew.Current.Token != right && ew.HasNext)
{
if (ew.Current.Token == ExpressionToken.Comma)
{
if (ew.HasBack && ew.PeakBack.Token == ExpressionToken.Comma)
{
exprs.Add(NullIdentity.Instance);
}
ew.NextOrThrow();
continue;
}
var expression = ParseExpression(ew, caller);
if (ew.IsCurrent(ExpressionToken.Colon))
{
//handle keyvalue item
exprs.Add(KeyValueExpression.Parse(ew, expression, caller));
}
else
{
exprs.Add(expression);
}
}
if (exprs.Count == 0 && !argsOptional)
{
throw new UnexpectedTokenException($"Was expecting an expression between {left} and {right}");
}
ew.Next();
args.Arguments = exprs.ToArray();
return(args);
}
public static ArgumentsExpression Parse(ExpressionWalker ew, Func <TokenMatch, bool> parseTill, bool argsOptional, Type caller = null)
{
var args = new ArgumentsExpression();
var exprs = new List <Expression>();
while (!parseTill(ew.Current) && ew.HasNext)
{
if (ew.Current.Token == ExpressionToken.Comma)
{
if (ew.HasBack && ew.PeakBack.Token == ExpressionToken.Comma)
{
exprs.Add(NullIdentity.Instance);
}
ew.NextOrThrow();
continue;
}
var expression = ParseExpression(ew, caller);
if (ew.IsCurrent(ExpressionToken.Colon))
{
//handle keyvalue item
exprs.Add(KeyValueExpression.Parse(ew, expression));
}
else
{
exprs.Add(expression);
}
}
if (exprs.Count == 0 && !argsOptional)
{
throw new UnexpectedTokenException($"Was expecting arguments but found none while argsOptional is false");
}
ew.Next();
args.Arguments = exprs.ToArray();
return(args);
}
public static IdentityExpression Parse(ExpressionWalker ew, Type caller = null, Expression left = null)
{
var ret = new IdentityExpression();
//types:
//justname
//justname.accessor
//justname.accessor[5].second
//justname.method().someval
//justname.method().someval[3].thatsfar
if (left == null)
{
ew.IsCurrentOrThrow(ExpressionToken.Literal);
}
if (ew.HasNext && ew.PeakNext.WhitespacesAfterMatch == 0 && ew.PeakNext.Token == ExpressionToken.Period && caller != typeof(IdentityExpression) || left != null)
{
var first = left ?? ParseExpression(ew, typeof(IdentityExpression));
ew.NextOrThrow(); //skip the predicted period.
var next = ew.PeakNext;
switch (next.Token)
{
//currently we are at Literal
case ExpressionToken.Period:
ret.Identity = new PropertyIdentity(first, Parse(ew));
return(ret);
case ExpressionToken.LeftBracet:
ret.Identity = new PropertyIdentity(first, IndexerCallExpression.Parse(ew));
return(ret);
case ExpressionToken.LeftParen:
ret.Identity = new PropertyIdentity(first, CallExpression.Parse(ew));
return(ret);
default:
if (left != null)
{
return(new IdentityExpression(new PropertyIdentity(left, Parse(ew, typeof(IdentityExpression), null))));
}
if (first != null)
{
//just a plain single word!
var right = new IdentityExpression();
if (ew.IsCurrent(ExpressionToken.Null))
{
right.Identity = NullIdentity.Instance;
}
else
{
ew.IsCurrentOrThrow(ExpressionToken.Literal);
right.Identity = StringIdentity.Create(ew.Current.Match);
}
ew.Next();
return(new IdentityExpression(new PropertyIdentity(first, right)));
}
goto _plain_identity;
}
}
_plain_identity:
//just a plain single word!
if (ew.IsCurrent(ExpressionToken.Null))
{
ret.Identity = NullIdentity.Instance;
}
else
{
ew.IsCurrentOrThrow(ExpressionToken.Literal);
ret.Identity = StringIdentity.Create(ew.Current.Match);
}
ew.Next();
return(ret);
}
public static Expression ParseExpression(ExpressionWalker ew, Type caller = null)
{
Expression ret = null;
_retry:
bool isOperatorCall = caller == typeof(OperatorExpression) || caller == typeof(RightOperatorExpression) || caller == typeof(ForeachExpression);
var current = ew.Current.Token;
if (current == ExpressionToken.Literal)
{
//cases like variable(.., variable[.., variable + .., variable
if (ew.HasNext)
{
var peak = ew.PeakNextOrThrow().Token;
if (peak == ExpressionToken.LeftParen)
{
ret = CallExpression.Parse(ew);
}
else if (peak == ExpressionToken.Period && caller != typeof(IdentityExpression) && caller != typeof(InteractableExpression))
{
ret = IdentityExpression.Parse(ew);
}
else if (peak == ExpressionToken.LeftBracet)
{
ret = IndexerCallExpression.Parse(ew);
}
else if (peak == ExpressionToken.New)
{
ret = NewExpression.Parse(ew);
}
else if (RightOperatorExpression.IsNextAnRightUniOperation(ew, caller) && caller != typeof(RightOperatorExpression))
{
ret = RightOperatorExpression.Parse(ew);
}
else if (OperatorExpression.IsNextAnOperation(ew) && !isOperatorCall)
{
ret = OperatorExpression.Parse(ew);
}
else
{
ret = IdentityExpression.Parse(ew, caller);
}
}
else
{
ret = IdentityExpression.Parse(ew, caller);
}
}
else if (LeftOperatorExpression.IsCurrentAnLeftUniOperation(ew))
{
ret = LeftOperatorExpression.Parse(ew);
}
else if (current == ExpressionToken.NumberLiteral)
{
ret = NumberLiteral.Parse(ew);
}
else if (current == ExpressionToken.StringLiteral)
{
ret = StringLiteral.Parse(ew);
}
else if (current == ExpressionToken.LeftParen)
{
ret = GroupExpression.Parse(ew, ExpressionToken.LeftParen, ExpressionToken.RightParen);
}
else if (current == ExpressionToken.LeftBracet)
{
ret = ArrayExpression.Parse(ew);
}
else if (current == ExpressionToken.New)
{
ret = NewExpression.Parse(ew);
}
else if (current == ExpressionToken.Boolean)
{
ret = BooleanLiteral.Parse(ew);
}
else if (current == ExpressionToken.CharLiteral)
{
ret = CharLiteral.Parse(ew);
}
else if (current == ExpressionToken.Throw)
{
ret = ThrowExpression.Parse(ew);
}
else if (current == ExpressionToken.Hashtag && ew.HasNext && ew.PeakNext.Token == ExpressionToken.NumberLiteral)
{
ret = HashtagReferenceExpression.Parse(ew, caller);
}
else if (current == ExpressionToken.Null)
{
ret = NullIdentity.Parse(ew);
}
else if (current == ExpressionToken.NewLine)
{
ew.NextOrThrow();
goto _retry;
}
else
{
throw new UnexpectedTokenException($"Token was not expected to be a {ew.Current.Token}");
}
_rereview:
//here we parse chained math operations
while (OperatorExpression.IsCurrentAnOperation(ew) && !isOperatorCall)
{
if (RightOperatorExpression.IsCurrentAnRightUniOperation(ew) && caller != typeof(OperatorExpression))
{
ret = RightOperatorExpression.Parse(ew, ret);
}
else if (OperatorExpression.IsCurrentAnOperation(ew))
{
ret = OperatorExpression.Parse(ew, ret);
}
}
if (ew.IsCurrent(ExpressionToken.Or) && caller != typeof(TernaryExpression) && caller != typeof(OperatorExpression))
{
ret = TernaryExpression.Parse(ew, ret);
}
if (ew.IsCurrent(ExpressionToken.LeftBracet))
{
ret = IndexerCallExpression.Parse(ew, ret);
goto _rereview;
}
if (ew.IsCurrent(ExpressionToken.LeftParen))
{
ret = CallExpression.Parse(ew, ret);
goto _rereview;
}
return(ret);
}
