internal static Symbol DecodeSubstitutionExpr(LNode expr, out LNode condition, out bool isParams, out bool refExistingVar)
{
condition = null;
isParams = false;
refExistingVar = false;
if (expr.Calls(S.Substitute, 1))
{
LNode id = expr.Args[0];
if (id.AttrNamed(S.Params) != null)
{
isParams = true;
}
else if (id.Calls(S.DotDotDot, 1) || id.Calls(S.DotDot, 1))
{
isParams = true;
id = id.Args[0];
}
if (id.AttrNamed(S.Ref) != null)
{
refExistingVar = true;
}
if (id.Calls(S.IndexBracks, 2))
{
// very old style
condition = id.Args[1];
id = id.Args[0];
}
else
{
while (id.Calls(S.And, 2) || id.Calls(S.When, 2))
{
// old style `&&` and new style `when`
condition = condition == null ? id.Args[1] : LNode.Call(CodeSymbols.And, LNode.List(id.Args[1], condition)).SetStyle(NodeStyle.Operator);
id = id.Args[0];
}
}
if (condition != null)
{
condition = condition.ReplaceRecursive(n => n.IsIdNamed(S._HashMark) ? id : null);
}
if (!id.IsId)
{
return(null);
}
return(id.Name);
}
return(null);
}
public static LNode static_matchCode(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) == null && !node.HasSpecialName)
return null; // handled by normal matchCode macro
var args_body = context.GetArgsAndBody(false);
VList<LNode> args = args_body.Item1, body = args_body.Item2;
if (args.Count != 1)
return Reject(context, args[1], "Expected only one expression to match");
var expression = context.PreProcess(AutoStripBraces(args[0]));
var cases = GetCases(body, context.Sink);
// The `default:` case is represented by an empty list of patterns.
if (cases.WithoutLast(1).Any(pair => pair.Key.IsEmpty))
context.Write(Severity.Error, node, "The `default:` case must be the last one, because the cases are tested in the order they appear, so no case after `default:` can be matched.");
MMap<Symbol, LNode> captures = new MMap<Symbol, LNode>();
foreach (Pair<VList<LNode>, VList<LNode>> pair in cases)
{
var patterns = pair.Key.IsEmpty ? new VList<LNode>((LNode)null) : pair.Key;
foreach (var pattern in patterns)
{
captures.Clear();
VList<LNode> _;
if (pattern == null || LNodeExt.MatchesPattern(expression, pattern, ref captures, out _)) {
captures[_hash] = expression; // define $#
captures.Remove(__);
return ReplaceCaptures(pair.Value.AsLNode(S.Splice), captures);
}
}
}
return F.Call(S.Splice); // none of the cases matched
}
public virtual LNode VisitInput(LNode stmt, IMessageSink sink)
{
LNode aliasSet;
if ((stmt.Calls(_alias, 1) || stmt.CallsMin(S.Alias, 1)) &&
(aliasSet = stmt.Args[0]).Calls(S.Assign, 2))
{
IEnumerable <KeyValuePair <LNode, LNode> > q;
LNode alias = aliasSet.Args[0], replacement = aliasSet.Args[1], old;
if (_definedAliases.TryGetValue(alias, out old))
{
if (stmt.AttrNamed(S.Partial) == null || !old.Equals(replacement))
{
sink.Warning(alias, "Redefinition of alias '{0}'", alias);
}
}
else if ((q = _definedAliases.Where(pair => replacement.Equals(pair.Value))).Any())
{
sink.Warning(replacement, "Aliases '{0}' and '{1}' have the same replacement value", q.First().Key, alias);
}
_definedAliases[alias] = replacement;
return(LNode.Call(S.Splice, VList <LNode> .Empty)); // erase alias from output
}
return(null);
}
public static LNode static_tryDeconstruct(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) == null && !node.HasSpecialName)
return Reject(context, node, "Expected 'static' attribute");
foreach (var arg in node.Args)
DoDeconstruct(arg, context, printErrorOnFailure: false);
return F.Call(S.Splice);
}
public static LNode StaticIf(LNode @if, IMacroContext context)
{
LNode @static;
if ((@static = @if.AttrNamed(S.Static)) == null || [email protected])
{
return(null);
}
return(static_if(@if, context));
}
static bool IsParamsCapture(LNode pattern)
{
if (pattern.Calls(S.Substitute, 1))
{
LNode arg = pattern.Args.Last;
return((arg.Calls(S.DotDot, 1) || arg.Calls(S.DotDotDot, 1) || arg.AttrNamed(S.Params) != null) &&
GetCaptureIdentifier(pattern) != null);
}
return(false);
}
public static LNode StaticIf(LNode @if, IMessageSink sink)
{
LNode @static;
if ((@static = @if.AttrNamed(S.Static)) == null || [email protected])
{
return(null);
}
return(static_if(@if, sink));
}
internal static Symbol GetSubstitutionVar(LNode expr, out LNode condition, out bool isParams, out bool refExistingVar)
{
condition = null;
isParams = false;
refExistingVar = false;
if (expr.Calls(S.Substitute, 1))
{
LNode id = expr.Args[0];
if (id.AttrNamed(S.Params) != null)
{
isParams = true;
}
else if (id.Calls(S.DotDot, 1))
{
isParams = true;
id = id.Args[0];
}
if (id.AttrNamed(S.Ref) != null)
{
refExistingVar = true;
}
if (id.Calls(S.IndexBracks, 2))
{
condition = id.Args[1];
id = id.Args[0];
}
else if (id.ArgCount == 1)
{
condition = id.Args[0];
id = id.Target;
}
if (condition != null)
{
condition = condition.ReplaceRecursive(n => n.IsIdNamed(S._HashMark) ? id : null);
}
if (!id.IsId)
{
return(null);
}
return(id.Name);
}
return(null);
}
public static LNode static_tryDeconstruct(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) == null && !node.HasSpecialName)
{
return(Reject(context, node, "Expected 'static' attribute"));
}
foreach (var arg in node.Args)
{
DoDeconstruct(arg, context, printErrorOnFailure: false);
}
return(F.Call(S.Splice));
}
public static LNode static_matchCode(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) == null && !node.HasSpecialName)
{
return(null); // handled by normal matchCode macro
}
var args_body = context.GetArgsAndBody(false);
VList <LNode> args = args_body.Item1, body = args_body.Item2;
if (args.Count != 1)
{
return(Reject(context, args[1], "Expected only one expression to match"));
}
var expression = context.PreProcess(AutoStripBraces(args[0]));
var cases = GetCases(body, context.Sink);
// The `default:` case is represented by an empty list of patterns.
if (cases.WithoutLast(1).Any(pair => pair.Key.IsEmpty))
{
context.Write(Severity.Error, node, "The `default:` case must be the last one, because the cases are tested in the order they appear, so no case after `default:` can be matched.");
}
MMap <Symbol, LNode> captures = new MMap <Symbol, LNode>();
foreach (Pair <VList <LNode>, VList <LNode> > pair in cases)
{
var patterns = pair.Key.IsEmpty ? new VList <LNode>((LNode)null) : pair.Key;
foreach (var pattern in patterns)
{
captures.Clear();
VList <LNode> _;
if (pattern == null || LNodeExt.MatchesPattern(expression, pattern, ref captures, out _))
{
captures[_hash] = expression; // define $#
captures.Remove(__);
return(ReplaceCaptures(pair.Value.AsLNode(S.Splice), captures));
}
}
}
return(F.Call(S.Splice)); // none of the cases matched
}
public static LNode StaticIf(LNode @if, IMessageSink sink)
{
LNode @static;
if ((@static = @if.AttrNamed(S.Static)) == null || [email protected])
return null;
return static_if(@if, sink);
}
public virtual LNode VisitInput(LNode stmt, IMessageSink sink)
{
LNode aliasSet;
if ((stmt.Calls(_alias, 1) || stmt.CallsMin(S.Alias, 1)) &&
(aliasSet = stmt.Args[0]).Calls(S.Assign, 2))
{
IEnumerable<KeyValuePair<LNode, LNode>> q;
LNode alias = aliasSet.Args[0], replacement = aliasSet.Args[1], old;
if (_definedAliases.TryGetValue(alias, out old)) {
if (stmt.AttrNamed(S.Partial) == null || !old.Equals(replacement))
sink.Write(Severity.Warning, alias, "Redefinition of alias '{0}'", alias);
} else if ((q = _definedAliases.Where(pair => replacement.Equals(pair.Value))).Any())
sink.Write(Severity.Warning, replacement, "Aliases '{0}' and '{1}' have the same replacement value", q.First().Key, alias);
_definedAliases[alias] = replacement;
return LNode.Call(S.Splice, RVList<LNode>.Empty); // erase alias from output
}
return null;
}
public static LNode matchCode(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) != null)
{
return(null); // this case is handled by static_matchCode macro
}
var args_body = context.GetArgsAndBody(false);
LNodeList args = args_body.Item1, body = args_body.Item2;
if (args.Count != 1 || body.Count < 1)
{
return(null);
}
var cases = GetCases(body, context.Sink);
if (cases.IsEmpty)
{
return(null);
}
var output = new WList <LNode>();
var var = MaybeAddTempVarDecl(context, args[0], output);
var ifClauses = new List <Pair <LNode, LNode> >();
var cmc = new CodeMatchContext {
Context = context
};
foreach (var @case in cases)
{
cmc.ThenClause.Clear();
// e.g. case [$(..._)] Foo($x + 1, $y) =>
// LNode x, y, tmp9;
// if (var.Calls((Symbol) "Foo", 2) && (tmp9 = var.Args[0]).Calls(CodeSymbols.Plus, 2)
// && (x = tmp9.Args[0]) != null // this will never be null, but we want to put it the assignment in the 'if' statement
// && 1.Equals(tmp9.Args[1].Value) && (y = var.Args[1]) != null) { ... }
LNode testExpr = null;
if (@case.Key.Count > 0)
{
if (cmc.IsMultiCase = @case.Key.Count > 1)
{
cmc.UsageCounters.Clear();
testExpr = @case.Key.Aggregate((LNode)null, (test, pattern) => {
test = LNode.MergeBinary(test, cmc.MakeTopTestExpr(pattern, var), S.Or);
return(test);
});
foreach (var pair in cmc.UsageCounters.Where(p => p.Value < @case.Key.Count))
{
if (cmc.NodeVars.ContainsKey(pair.Key))
{
cmc.NodeVars[pair.Key] = true;
}
if (cmc.ListVars.ContainsKey(pair.Key))
{
cmc.ListVars[pair.Key] = true;
}
}
}
else
{
testExpr = cmc.MakeTopTestExpr(@case.Key[0], var);
}
}
var handler = F.Braces(@case.Value);
if (cmc.ThenClause.Count > 0)
{
handler = LNode.MergeLists(F.Braces(cmc.ThenClause), handler, S.Braces);
}
ifClauses.Add(Pair.Create(testExpr, handler));
}
LNode ifStmt = null;
for (int i = ifClauses.Count - 1; i >= 0; i--)
{
if (ifClauses[i].Item1 == null)
{
if (ifStmt == null)
{
ifStmt = ifClauses[i].Item2;
}
else
{
context.Sink.Error(node, "The default case must appear last, and there can be only one.");
}
}
else
{
if (ifStmt == null)
{
ifStmt = F.Call(S.If, ifClauses[i].Item1, ifClauses[i].Item2);
}
else
{
ifStmt = F.Call(S.If, ifClauses[i].Item1, ifClauses[i].Item2, ifStmt);
}
}
}
if (cmc.NodeVars.Count > 0)
{
output.Add(F.Call(S.Var, ListExt.Single(F.Id("LNode")).Concat(
cmc.NodeVars.OrderBy(v => v.Key.Name).Select(kvp => kvp.Value ? F.Call(S.Assign, F.Id(kvp.Key), F.Null) : F.Id(kvp.Key)))));
}
if (cmc.ListVars.Count > 0)
{
LNode type = LNode.Id((Symbol)"LNodeList");
output.Add(F.Call(S.Var, ListExt.Single(type).Concat(
cmc.ListVars.OrderBy(v => v.Key.Name).Select(kvp => kvp.Value ? LNode.Call(CodeSymbols.Assign, LNode.List(F.Id(kvp.Key), LNode.Call(CodeSymbols.Default, LNode.List(type)))).SetStyle(NodeStyle.Operator) : F.Id(kvp.Key)))));
}
if (output.Count == 0)
{
return(ifStmt.IncludingTriviaFrom(node));
}
else
{
output.Add(ifStmt);
return(F.Braces(output.ToVList()).IncludingTriviaFrom(node));
}
}
void GetPatternComponents(LNode pattern, out LNode varBinding, out bool refExistingVar, out LNode cmpExpr, out LNode isType, out LNode inRange, out VList <LNode> subPatterns, out VList <LNode> conditions)
{
// Here's a typical pattern (case expr):
// is Shape(ShapeType.Circle, ref size, Location: p is Point<int>(x, y)):
// When there is an arg list, we decode its Target and return the args.
//
// The caller is in charge of stripping out "Property:" prefix, if any,
// so the most complex pattern that this method considers is something
// like `(expr is Type in Range)(subPatterns) && conds` where `expr` is
// a varName or $varName to deconstruct, or some expression to test for
// equality. Assuming it's an equality test, the output will be
//
// varBinding = null
// refExistingVar = false
// cmpExpr = quote(expr);
// isType = quote(Type);
// inRange = quote(Range);
// conds will have "conds" pushed to the front.
//
bool haveSubPatterns = false;
subPatterns = VList <LNode> .Empty;
refExistingVar = pattern.AttrNamed(S.Ref) != null;
// First, look for "pattern && condition"
conditions = VList <LNode> .Empty;
while (pattern.Calls(S.And, 2))
{
conditions.Add(pattern.Args.Last);
pattern = pattern.Args[0];
}
LNode cmpExprOrBinding = null;
varBinding = cmpExpr = isType = inRange = null;
// Now decode the expression. Use three passes, each of which decodes
// an "outer" layer such as A is B, A in B, or expr(args). Since you
// can combine these operators, we may need multiple passes (e.g.
// "X is T in R" and "X in R is T" are equivalent), and keep in mind
// that operator trees like "A in B" are nearly identical to prefix-
// calls like "foo(A, B)" except for the call target and the `BaseStyle`.
for (int pass = 1; pass <= 3; pass++)
{
LNode inRange2 = inRange, isType2 = isType;
{
LNode patternL;
if (pattern.Calls(CodeSymbols.In, 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls((Symbol)"in", 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null)
{
pattern = patternL;
if (inRange2 != null)
{
_context.Sink.Error(inRange2, "match-case does not support multiple 'in' operators");
}
}
else if (pattern.Calls(CodeSymbols.Is, 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null || pattern.Calls((Symbol)"is", 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null)
{
pattern = cmpExprOrBinding;
if (isType2 != null)
{
_context.Sink.Error(isType2, "match-case does not support multiple 'is' operators");
}
}
else if (pattern.Calls(CodeSymbols.Is, 1) && (isType = pattern.Args[0]) != null || pattern.Calls((Symbol)"is", 1) && (isType = pattern.Args[0]) != null)
{
if (isType2 != null)
{
_context.Sink.Error(isType2, "match-case does not support multiple 'is' operators");
}
goto doneAnalysis;
}
else if (pattern.Calls(CodeSymbols.DotDotDot, 2) || pattern.Calls(CodeSymbols.DotDot, 2) || pattern.Calls(CodeSymbols.DotDotDot, 1) || pattern.Calls(CodeSymbols.DotDot, 1))
{
inRange = pattern;
goto doneAnalysis;
}
else if (pattern.Calls(CodeSymbols.Tuple))
{
subPatterns = pattern.Args;
cmpExprOrBinding = null;
}
else
{
// It's very tempting to detect NodeStyle.PrefixNotation to distinguish,
// say, A.B<C> from id(A, B, C), but I'm reluctant to do so. BaseStyle
// is by convention "unsemantic" and not guaranteed to be preserved
// across serializations or supported the same way by different parsers.
// So instead of asking "is this in PrefixNotation?" I ask "does the
// target appear to be a normal identifier?"
LNode target = pattern.Target;
if (!haveSubPatterns && pattern.IsCall && (!target.IsId || target.AttrNamed(S.TriviaInParens) != null || (!target.HasSpecialName && Les2Printer.IsNormalIdentifier(target.Name)))
)
{
haveSubPatterns = true;
subPatterns = pattern.Args;
pattern = pattern.Target;
}
else
{
cmpExprOrBinding = pattern;
}
}
}
}
doneAnalysis:
if (cmpExprOrBinding != null)
{
if (cmpExprOrBinding.Calls(S.Substitute, 1))
{
varBinding = cmpExprOrBinding[0];
}
else if (refExistingVar)
{
varBinding = cmpExprOrBinding;
}
else if ((varBinding ?? cmpExprOrBinding).IsIdNamed(__))
{
cmpExprOrBinding = varBinding = null;
}
// Originally a plain identifier would be a binding, like $identifier
//if (cmpExprOrBinding.IsId && cmpExprOrBinding.AttrNamed(S.TriviaInParens) == null)
// varBinding = cmpExprOrBinding;
if (varBinding != null)
{
if (varBinding.AttrNamed(S.Ref) != null)
{
refExistingVar = true;
varBinding = varBinding.WithoutAttrs();
}
if (!varBinding.IsId)
{
_context.Sink.Error(varBinding, "Invalid variable name in match-case: {0}", varBinding);
varBinding = null;
}
}
if (varBinding == null)
{
cmpExpr = cmpExprOrBinding;
}
}
if (refExistingVar && varBinding == null)
{
refExistingVar = false;
var got = cmpExprOrBinding ?? pattern;
_context.Sink.Warning(got, "'ref' expected a variable name (got `{0}`)", got);
}
}
public SPResult AutoPrintMethodDefinition(Ambiguity flags)
{
// S.Fn, S.Delegate: #fn(#int32, Square, #(int x), { return x * x; });
if (EcsValidators.MethodDefinitionKind(_n, true, Pedantics) == null)
{
return(SPResult.Fail);
}
LNode retType = _n.Args[0], name = _n.Args[1];
LNode args = _n.Args[2];
LNode body = _n.Args[3, null];
bool isConstructor = _n.Name == S.Constructor;
bool isDestructor = !isConstructor && name.Calls(S._Destruct, 1);
LNode firstStmt = null;
if (isConstructor && body != null && body.CallsMin(S.Braces, 1))
{
// Detect ": this(...)" or ": base(...)"
firstStmt = body.Args[0];
if (!CallsWPAIH(firstStmt, S.This) &&
!CallsWPAIH(firstStmt, S.Base))
{
firstStmt = null;
}
}
if (!AllowConstructorAmbiguity)
{
if (isDestructor && _spaceName == S.Fn)
{
// When destructor syntax is ambiguous, use prefix notation.
return(SPResult.Fail);
}
else if (isConstructor && firstStmt == null)
{
// When constructor syntax is ambiguous, use prefix notation.
if (name.IsIdNamed(S.This))
{
if (_spaceName == S.Fn)
{
return(SPResult.Fail);
}
}
else if (!name.IsIdNamed(_spaceName))
{
return(SPResult.Fail);
}
}
}
// A cast operator with the structure: #fn(Foo, operator`#cast`, #(...))
// can be printed in a special format: operator Foo(...);
bool isCastOperator = (name.Name == S.Cast && name.AttrNamed(S.TriviaUseOperatorKeyword) != null);
var ifClause = PrintTypeAndName(isConstructor || isDestructor, isCastOperator,
isConstructor && !name.IsIdNamed(S.This) ? AttrStyle.IsConstructor : AttrStyle.IsDefinition);
PrintArgList(args.Args, ParenFor.MethodDecl, Ambiguity.AllowUnassignedVarDecl, OmitMissingArguments);
PrintWhereClauses(name);
// If this is a constructor where the first statement is this(...) or
// base(...), we must change the notation to ": this(...) {...}" as
// required in plain C#
if (firstStmt != null)
{
using (Indented) {
if (!Newline(NewlineOpt.BeforeConstructorColon))
{
Space(SpaceOpt.BeforeConstructorColon);
}
WriteThenSpace(':', SpaceOpt.AfterColon);
PrintExpr(firstStmt, StartExpr, Ambiguity.NoBracedBlock);
}
}
return(AutoPrintBodyOfMethodOrProperty(body, ifClause, firstStmt != null));
}
private bool IsDefaultNewlineSuppressed(LNode node)
{
return(node.AttrNamed(S.TriviaAppendStatement) != null);
}
public static LNode matchCode(LNode node, IMacroContext context)
{
if (node.AttrNamed(S.Static) != null)
return null; // this case is handled by static_matchCode macro
var args_body = context.GetArgsAndBody(false);
VList<LNode> args = args_body.Item1, body = args_body.Item2;
if (args.Count != 1 || body.Count < 1)
return null;
var cases = GetCases(body, context.Sink);
if (cases.IsEmpty)
return null;
var output = new WList<LNode>();
var @var = MaybeAddTempVarDecl(context, args[0], output);
var ifClauses = new List<Pair<LNode, LNode>>();
var cmc = new CodeMatchContext {
Context = context
};
foreach (var @case in cases)
{
cmc.ThenClause.Clear();
// e.g. case [$(..._)] Foo($x + 1, $y) =>
// LNode x, y, tmp9;
// if (var.Calls((Symbol) "Foo", 2) && (tmp9 = var.Args[0]).Calls(CodeSymbols.Plus, 2)
// && (x = tmp9.Args[0]) != null // this will never be null, but we want to put it the assignment in the 'if' statement
// && 1.Equals(tmp9.Args[1].Value) && (y = var.Args[1]) != null) { ... }
LNode testExpr = null;
if (@case.Key.Count > 0) {
if (cmc.IsMultiCase = @case.Key.Count > 1) {
cmc.UsageCounters.Clear();
testExpr = @case.Key.Aggregate((LNode) null, (test, pattern) => {
test = LNode.MergeBinary(test, cmc.MakeTopTestExpr(pattern, @var), S.Or);
return test;
});
foreach (var pair in cmc.UsageCounters.Where(p => p.Value < @case.Key.Count)) {
if (cmc.NodeVars.ContainsKey(pair.Key))
cmc.NodeVars[pair.Key] = true;
if (cmc.ListVars.ContainsKey(pair.Key))
cmc.ListVars[pair.Key] = true;
}
} else
testExpr = cmc.MakeTopTestExpr(@case.Key[0], @var);
}
var handler = @case.Value.AsLNode(S.Braces);
if (cmc.ThenClause.Count > 0)
handler = LNode.MergeLists(F.Braces(cmc.ThenClause), handler, S.Braces);
ifClauses.Add(Pair.Create(testExpr, handler));
}
LNode ifStmt = null;
for (int i = ifClauses.Count - 1; i >= 0; i--)
{
if (ifClauses[i].Item1 == null) {
if (ifStmt == null)
ifStmt = ifClauses[i].Item2;
else
context.Sink.Error(node, "The default case must appear last, and there can be only one.");
} else {
if (ifStmt == null)
ifStmt = F.Call(S.If, ifClauses[i].Item1, ifClauses[i].Item2);
else
ifStmt = F.Call(S.If, ifClauses[i].Item1, ifClauses[i].Item2, ifStmt);
}
}
if (cmc.NodeVars.Count > 0)
output.Add(F.Call(S.Var, ListExt.Single(F.Id("LNode")).Concat(
cmc.NodeVars.OrderBy(v => v.Key.Name).Select(kvp => kvp.Value ? F.Call(S.Assign, F.Id(kvp.Key), F.Null) : F.Id(kvp.Key)))));
if (cmc.ListVars.Count > 0) {
LNode type = LNode.Call(CodeSymbols.Of, LNode.List(LNode.Id((Symbol) "VList"), LNode.Id((Symbol) "LNode"))).SetStyle(NodeStyle.Operator);
output.Add(F.Call(S.Var, ListExt.Single(type).Concat(
cmc.ListVars.OrderBy(v => v.Key.Name).Select(kvp => kvp.Value ? LNode.Call(CodeSymbols.Assign, LNode.List(F.Id(kvp.Key), LNode.Call(CodeSymbols.Default, LNode.List(type)))).SetStyle(NodeStyle.Operator) : F.Id(kvp.Key)))));
}
if (output.Count == 0)
return ifStmt;
else {
output.Add(ifStmt);
return F.Braces(output.ToVList());
}
}
private bool IsDefaultNewlineSuppressed(LNode node)
{
return node.AttrNamed(S.TriviaAppendStatement) != null || (_flags & Ambiguity.OneLiner) != 0;
}
public static LNode StaticIf(LNode @if, IMacroContext context)
{
LNode @static;
if ((@static = @if.AttrNamed(S.Static)) == null || [email protected])
return null;
return static_if(@if, context);
}
public static LNode BackingField(LNode prop, IMessageSink sink)
{
LNode type, name, body;
if (prop.ArgCount != 3 || !(body = prop.Args[2]).Calls(S.Braces))
{
return(null);
}
LNode fieldAttr = null, fieldVarAttr = null;
LNode fieldName;
bool autoType = false;
int i;
for (i = 0; i < prop.Attrs.Count; i++)
{
LNode attr = prop.Attrs[i];
if (attr.IsIdNamed(_field) ||
attr.Calls(S.Var, 2) &&
((autoType = attr.Args[0].IsIdNamed(_field)) ||
(fieldVarAttr = attr.AttrNamed(_field)) != null && fieldVarAttr.IsId))
{
fieldAttr = attr;
break;
}
}
if (fieldAttr == null)
{
return(null);
}
LNode field = fieldAttr;
type = prop.Args[0];
if (field.IsId)
{
name = prop.Args[1];
fieldName = F.Id(ChooseFieldName(Ecs.EcsNodePrinter.KeyNameComponentOf(name)));
field = F.Call(S.Var, type, fieldName).WithAttrs(fieldAttr.Attrs);
}
else
{
fieldName = field.Args[1];
if (fieldName.Calls(S.Assign, 2))
{
fieldName = fieldName.Args[0];
}
}
if (autoType)
{
field = field.WithArgChanged(0, type);
}
if (fieldVarAttr != null)
{
field = field.WithoutAttrNamed(_field);
}
LNode newBody = body.WithArgs(body.Args.SmartSelect(stmt =>
{
var attrs = stmt.Attrs;
if (stmt.IsIdNamed(S.get))
{
stmt = F.Call(stmt.WithoutAttrs(), F.Braces(F.Call(S.Return, fieldName))).WithAttrs(attrs);
stmt.BaseStyle = NodeStyle.Special;
}
if (stmt.IsIdNamed(S.set))
{
stmt = F.Call(stmt.WithoutAttrs(), F.Braces(F.Call(S.Assign, fieldName, F.Id(S.value)))).WithAttrs(attrs);
stmt.BaseStyle = NodeStyle.Special;
}
return(stmt);
}));
if (newBody == body)
{
sink.Write(Severity.Warning, fieldAttr, "The body of the property does not contain a 'get;' or 'set;' statement without a body, so no code was generated to get or set the backing field.");
}
prop = prop.WithAttrs(prop.Attrs.RemoveAt(i)).WithArgChanged(2, newBody);
return(F.Call(S.Splice, new RVList <LNode>(field, prop)));
}
public static bool IsParenthesizedExpr(this LNode node)
{
return(node.AttrNamed(CodeSymbols.TriviaInParens) != null);
}
void GetPatternComponents(LNode pattern, out LNode varBinding, out bool refExistingVar, out LNode cmpExpr, out LNode isType, out LNode inRange, out VList<LNode> subPatterns, out VList<LNode> conditions)
{
// Here's a typical pattern (case expr):
// is Shape(ShapeType.Circle, ref size, Location: p is Point<int>(x, y)):
// When there is an arg list, we decode its Target and return the args.
//
// The caller is in charge of stripping out "Property:" prefix, if any,
// so the most complex pattern that this method considers is something
// like `(expr is Type in Range)(subPatterns) && conds` where `expr` is
// a varName or $varName to deconstruct, or some expression to test for
// equality. Assuming it's an equality test, the output will be
//
// varBinding = null
// refExistingVar = false
// cmpExpr = quote(expr);
// isType = quote(Type);
// inRange = quote(Range);
// conds will have "conds" pushed to the front.
//
bool haveSubPatterns = false;
subPatterns = VList<LNode>.Empty;
refExistingVar = pattern.AttrNamed(S.Ref) != null;
// First, look for "pattern && condition"
conditions = VList<LNode>.Empty;
while (pattern.Calls(S.And, 2)) {
conditions.Add(pattern.Args.Last);
pattern = pattern.Args[0];
}
LNode cmpExprOrBinding = null;
varBinding = cmpExpr = isType = inRange = null;
// Now decode the expression. Use three passes, each of which decodes
// an "outer" layer such as A is B, A in B, or expr(args). Since you
// can combine these operators, we may need multiple passes (e.g.
// "X is T in R" and "X in R is T" are equivalent), and keep in mind
// that operator trees like "A in B" are nearly identical to prefix-
// calls like "foo(A, B)" except for the call target and the `BaseStyle`.
for (int pass = 1; pass <= 3; pass++) {
LNode inRange2 = inRange, isType2 = isType;
{
LNode patternL;
if (pattern.Calls(CodeSymbols.In, 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls((Symbol) "in", 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null) {
pattern = patternL;
if (inRange2 != null)
_context.Sink.Error(inRange2, "match-case does not support multiple 'in' operators");
} else if (pattern.Calls(CodeSymbols.Is, 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null || pattern.Calls((Symbol) "is", 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null) {
pattern = cmpExprOrBinding;
if (isType2 != null)
_context.Sink.Error(isType2, "match-case does not support multiple 'is' operators");
} else if (pattern.Calls(CodeSymbols.Is, 1) && (isType = pattern.Args[0]) != null || pattern.Calls((Symbol) "is", 1) && (isType = pattern.Args[0]) != null) {
if (isType2 != null)
_context.Sink.Error(isType2, "match-case does not support multiple 'is' operators");
goto doneAnalysis;
} else if (pattern.Calls(CodeSymbols.DotDotDot, 2) || pattern.Calls(CodeSymbols.DotDot, 2) || pattern.Calls(CodeSymbols.DotDotDot, 1) || pattern.Calls(CodeSymbols.DotDot, 1)) {
inRange = pattern;
goto doneAnalysis;
} else if (pattern.Calls(CodeSymbols.Tuple)) {
subPatterns = pattern.Args;
cmpExprOrBinding = null;
} else {
// It's very tempting to detect NodeStyle.PrefixNotation to distinguish,
// say, A.B<C> from id(A, B, C), but I'm reluctant to do so. BaseStyle
// is by convention "unsemantic" and not guaranteed to be preserved
// across serializations or supported the same way by different parsers.
// So instead of asking "is this in PrefixNotation?" I ask "does the
// target appear to be a normal identifier?"
LNode target = pattern.Target;
if (!haveSubPatterns && pattern.IsCall && (!target.IsId || target.AttrNamed(S.TriviaInParens) != null || (!target.HasSpecialName && Les2Printer.IsNormalIdentifier(target.Name)))
)
{
haveSubPatterns = true;
subPatterns = pattern.Args;
pattern = pattern.Target;
} else
cmpExprOrBinding = pattern;
}
}
}
doneAnalysis:
if (cmpExprOrBinding != null) {
if (cmpExprOrBinding.Calls(S.Substitute, 1))
varBinding = cmpExprOrBinding[0];
else if (refExistingVar)
varBinding = cmpExprOrBinding;
else if ((varBinding ?? cmpExprOrBinding).IsIdNamed(__))
cmpExprOrBinding = varBinding = null;
// Originally a plain identifier would be a binding, like $identifier
//if (cmpExprOrBinding.IsId && cmpExprOrBinding.AttrNamed(S.TriviaInParens) == null)
// varBinding = cmpExprOrBinding;
if (varBinding != null) {
if (varBinding.AttrNamed(S.Ref) != null) {
refExistingVar = true;
varBinding = varBinding.WithoutAttrs();
}
if (!varBinding.IsId) {
_context.Sink.Error(varBinding, "Invalid variable name in match-case: {0}", varBinding);
varBinding = null;
}
}
if (varBinding == null)
cmpExpr = cmpExprOrBinding;
}
if (refExistingVar && varBinding == null) {
refExistingVar = false;
var got = cmpExprOrBinding ?? pattern;
_context.Sink.Warning(got, "'ref' expected a variable name (got `{0}`)", got);
}
}
void GetPatternComponents(LNode pattern, out LNode varBinding, out bool refExistingVar, out LNode cmpExpr, out LNode isType, out LNode inRange, out VList<LNode> subPatterns, out VList<LNode> conditions)
{
bool haveSubPatterns = false;
subPatterns = VList<LNode>.Empty;
refExistingVar = pattern.AttrNamed(S.Ref) != null;
conditions = VList<LNode>.Empty;
while (pattern.Calls(S.And, 2)) {
conditions.Add(pattern.Args.Last);
pattern = pattern.Args[0];
}
LNode cmpExprOrBinding = null;
varBinding = cmpExpr = isType = inRange = null;
for (int pass = 1; pass <= 3; pass++) {
LNode inRange2 = inRange, isType2 = isType;
{
LNode patternL;
if (pattern.Calls(CodeSymbols.In, 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls((Symbol) "in", 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null) {
pattern = patternL;
if (inRange2 != null)
_context.Write(Severity.Error, inRange2, "match-case does not support multiple 'in' operators");
} else if (pattern.Calls(CodeSymbols.Is, 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null || pattern.Calls((Symbol) "is", 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null) {
pattern = cmpExprOrBinding;
if (isType2 != null)
_context.Write(Severity.Error, isType2, "match-case does not support multiple 'is' operators");
} else if (pattern.Calls(CodeSymbols.Is, 1) && (isType = pattern.Args[0]) != null || pattern.Calls((Symbol) "is", 1) && (isType = pattern.Args[0]) != null) {
if (isType2 != null)
_context.Write(Severity.Error, isType2, "match-case does not support multiple 'is' operators");
goto doneAnalysis;
} else if (pattern.Calls(CodeSymbols.DotDotDot, 2) || pattern.Calls(CodeSymbols.DotDot, 2) || pattern.Calls(CodeSymbols.DotDotDot, 1) || pattern.Calls(CodeSymbols.DotDot, 1)) {
inRange = pattern;
goto doneAnalysis;
} else if (pattern.Calls(CodeSymbols.Tuple)) {
subPatterns = pattern.Args;
cmpExprOrBinding = null;
} else {
LNode target = pattern.Target;
if (!haveSubPatterns && pattern.IsCall && (!target.IsId || target.AttrNamed(S.TriviaInParens) != null || (!target.HasSpecialName && LesNodePrinter.IsNormalIdentifier(target.Name)))) {
haveSubPatterns = true;
subPatterns = pattern.Args;
pattern = pattern.Target;
} else
cmpExprOrBinding = pattern;
}
}
}
doneAnalysis:
if (cmpExprOrBinding != null) {
if (cmpExprOrBinding.Calls(S.Substitute, 1))
varBinding = cmpExprOrBinding[0];
else if (refExistingVar)
varBinding = cmpExprOrBinding;
else if ((varBinding ?? cmpExprOrBinding).IsIdNamed(__))
cmpExprOrBinding = varBinding = null;
if (varBinding != null) {
if (varBinding.AttrNamed(S.Ref) != null) {
refExistingVar = true;
varBinding = varBinding.WithoutAttrs();
}
if (!varBinding.IsId) {
_context.Write(Severity.Error, varBinding, "Invalid variable name in match-case: {0}", varBinding);
varBinding = null;
}
}
if (varBinding == null)
cmpExpr = cmpExprOrBinding;
}
if (refExistingVar && varBinding == null) {
refExistingVar = false;
var got = cmpExprOrBinding ?? pattern;
_context.Write(Severity.Warning, got, "'ref' expected a variable name (got `{0}`)", got);
}
}
void GetPatternComponents(LNode pattern, out LNode propName,
out LNode varBinding, out bool refExistingVar,
out LNode cmpExpr, out LNode isType, out LNode inRange,
out VList <LNode> subPatterns, out VList <LNode> conditions)
{
// Format: PropName: is DerivedClass name(...) in Range
// Here's a typical pattern (case expr):
// is Shape(ShapeType.Circle, ref size, Location: p is Point<int>(x, y))
// When there is an arg list, we decode its Target and return the args.
//
// The caller is in charge of stripping out "Property:" prefix, if any,
// so the most complex pattern that this method considers is something
// like `expr is Type x(subPatterns) in Range && conds` where `expr` is
// a varName or $varName to deconstruct, or some expression to test for
// equality. Assuming it's an equality test, the output will be
//
// varBinding = null
// refExistingVar = false
// cmpExpr = quote(expr);
// isType = quote(Type);
// inRange = quote(Range);
// conds will have "conds" pushed to the front.
//
subPatterns = VList <LNode> .Empty;
refExistingVar = pattern.AttrNamed(S.Ref) != null;
propName = varBinding = cmpExpr = isType = inRange = null;
// Deconstruct `PropName: pattern` (fun fact: we can't use `matchCode`
// to detect a named parameter here, because if we write
// `case { $propName: $subPattern; }:` it is parsed as a goto-label,
// not as a named parameter.)
if (pattern.Calls(S.NamedArg, 2) || pattern.Calls(S.Colon, 2))
{
propName = pattern[0]; pattern = pattern[1];
}
// Deconstruct `pattern && condition` (iteratively)
conditions = VList <LNode> .Empty;
while (pattern.Calls(S.And, 2))
{
conditions.Add(pattern.Args.Last);
pattern = pattern.Args[0];
}
{
LNode lhs;
if (pattern.Calls(CodeSymbols.In, 2) && (lhs = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls((Symbol)"in", 2) && (lhs = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls(CodeSymbols.In, 2) && (lhs = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null)
{
pattern = lhs;
}
}
// Deconstruct `PropName is Type` with optional list of subpatterns.
// In LES let's accept ``PropName `is` (Type `with` (subpatterns))`` instead.
LNode subpatterns = null;
{
LNode lhs, type;
if (pattern.Calls(CodeSymbols.Is, 2) && (lhs = pattern.Args[0]) != null && (type = pattern.Args[1]) != null || pattern.Calls(CodeSymbols.Is, 3) && (lhs = pattern.Args[0]) != null && (type = pattern.Args[1]) != null && (subpatterns = pattern.Args[2]) != null || pattern.Calls((Symbol)"is", 2) && (lhs = pattern.Args[0]) != null && (type = pattern.Args[1]) != null || pattern.Calls((Symbol)"'is", 2) && (lhs = pattern.Args[0]) != null && (type = pattern.Args[1]) != null)
{
if (subpatterns == null)
{
if (type.Calls((Symbol)"with", 2) && (isType = type.Args[0]) != null && (subpatterns = type.Args[1]) != null || type.Calls((Symbol)"'with", 2) && (isType = type.Args[0]) != null && (subpatterns = type.Args[1]) != null)
{
}
}
if (type.Calls(CodeSymbols.Var, 2) && (isType = type.Args[0]) != null && (varBinding = type.Args[1]) != null)
{
}
else
{
isType = type;
}
if (lhs.Calls(S.Substitute, 1))
{
if (varBinding != null)
{
_context.Sink.Error(varBinding, "match: cannot bind two variable names to one value");
}
varBinding = lhs[0];
}
else if (propName != null)
{
_context.Sink.Error(varBinding, "match: property name already set to {0}", propName.Name);
if (varBinding == null)
{
varBinding = lhs; // assume it was intended as a variable binding
}
}
if (type.IsIdNamed("") // is var x
)
{
isType = null;
}
}
else if (pattern.Calls(CodeSymbols.DotDotDot, 2) || pattern.Calls(CodeSymbols.DotDot, 2) || pattern.Calls(CodeSymbols.DotDotDot, 1) || pattern.Calls(CodeSymbols.DotDot, 1))
{
inRange = pattern;
}
else if (pattern.Calls(CodeSymbols.AltList) || pattern.Calls(CodeSymbols.Tuple))
{
subpatterns = pattern;
}
else if (pattern.Calls(S.Substitute, 1))
{
varBinding = pattern[0];
}
else
{
cmpExpr = pattern;
}
}
if (subpatterns != null)
{
if (subpatterns.Calls(S.Tuple) || subpatterns.Calls(S.AltList))
{
subPatterns = subpatterns.Args;
}
else
{
_context.Sink.Error(subpatterns, "match: expected list of subpatterns (at '{0}')", subpatterns);
}
}
if (cmpExpr != null)
{
if (cmpExpr.IsIdNamed(__))
{
cmpExpr = null;
}
else if (refExistingVar && varBinding == null) // Treat `ref expr` as var binding
{
varBinding = cmpExpr;
cmpExpr = null;
}
}
if (varBinding != null)
{
if (varBinding.AttrNamed(S.Ref) != null)
{
varBinding = varBinding.WithoutAttrNamed(S.Ref);
refExistingVar = true;
}
else if (varBinding.IsIdNamed(__))
{
varBinding = null;
}
else if (!varBinding.IsId)
{
_context.Sink.Error(varBinding, "match: expected variable name (at '{0}')", varBinding);
varBinding = null;
}
}
}
void GetPatternComponents(LNode pattern, out LNode varBinding, out bool refExistingVar, out LNode cmpExpr, out LNode isType, out LNode inRange, out VList <LNode> subPatterns, out VList <LNode> conditions)
{
bool haveSubPatterns = false;
subPatterns = VList <LNode> .Empty;
refExistingVar = pattern.AttrNamed(S.Ref) != null;
conditions = VList <LNode> .Empty;
while (pattern.Calls(S.And, 2))
{
conditions.Add(pattern.Args.Last);
pattern = pattern.Args[0];
}
LNode cmpExprOrBinding = null;
varBinding = cmpExpr = isType = inRange = null;
for (int pass = 1; pass <= 3; pass++)
{
LNode inRange2 = inRange, isType2 = isType;
{
LNode patternL;
if (pattern.Calls(CodeSymbols.In, 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null || pattern.Calls((Symbol)"in", 2) && (patternL = pattern.Args[0]) != null && (inRange = pattern.Args[1]) != null)
{
pattern = patternL;
if (inRange2 != null)
{
_context.Write(Severity.Error, inRange2, "match-case does not support multiple 'in' operators");
}
}
else if (pattern.Calls(CodeSymbols.Is, 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null || pattern.Calls((Symbol)"is", 2) && (cmpExprOrBinding = pattern.Args[0]) != null && (isType = pattern.Args[1]) != null)
{
pattern = cmpExprOrBinding;
if (isType2 != null)
{
_context.Write(Severity.Error, isType2, "match-case does not support multiple 'is' operators");
}
}
else if (pattern.Calls(CodeSymbols.Is, 1) && (isType = pattern.Args[0]) != null || pattern.Calls((Symbol)"is", 1) && (isType = pattern.Args[0]) != null)
{
if (isType2 != null)
{
_context.Write(Severity.Error, isType2, "match-case does not support multiple 'is' operators");
}
goto doneAnalysis;
}
else if (pattern.Calls(CodeSymbols.DotDotDot, 2) || pattern.Calls(CodeSymbols.DotDot, 2) || pattern.Calls(CodeSymbols.DotDotDot, 1) || pattern.Calls(CodeSymbols.DotDot, 1))
{
inRange = pattern;
goto doneAnalysis;
}
else if (pattern.Calls(CodeSymbols.Tuple))
{
subPatterns = pattern.Args;
cmpExprOrBinding = null;
}
else
{
LNode target = pattern.Target;
if (!haveSubPatterns && pattern.IsCall && (!target.IsId || target.AttrNamed(S.TriviaInParens) != null || (!target.HasSpecialName && LesNodePrinter.IsNormalIdentifier(target.Name))))
{
haveSubPatterns = true;
subPatterns = pattern.Args;
pattern = pattern.Target;
}
else
{
cmpExprOrBinding = pattern;
}
}
}
}
doneAnalysis:
if (cmpExprOrBinding != null)
{
if (cmpExprOrBinding.Calls(S.Substitute, 1))
{
varBinding = cmpExprOrBinding[0];
}
else if (refExistingVar)
{
varBinding = cmpExprOrBinding;
}
else if ((varBinding ?? cmpExprOrBinding).IsIdNamed(__))
{
cmpExprOrBinding = varBinding = null;
}
if (varBinding != null)
{
if (varBinding.AttrNamed(S.Ref) != null)
{
refExistingVar = true;
varBinding = varBinding.WithoutAttrs();
}
if (!varBinding.IsId)
{
_context.Write(Severity.Error, varBinding, "Invalid variable name in match-case: {0}", varBinding);
varBinding = null;
}
}
if (varBinding == null)
{
cmpExpr = cmpExprOrBinding;
}
}
if (refExistingVar && varBinding == null)
{
refExistingVar = false;
var got = cmpExprOrBinding ?? pattern;
_context.Write(Severity.Warning, got, "'ref' expected a variable name (got `{0}`)", got);
}
}
private bool IsDefaultNewlineSuppressed(LNode node)
{
return(node.AttrNamed(S.TriviaAppendStatement) != null || (_flags & Ambiguity.OneLiner) != 0);
}
Pred BranchToPred(LNode expr, out BranchMode mode, Context ctx)
{
if (expr.Calls(_Default, 1) || expr.Calls(_Default2, 1)) {
expr = expr.Args[0];
mode = BranchMode.Default;
} else if (expr.Calls(_Error, 1) || expr.IsIdNamed(_DefaultError)) {
mode = (expr.AttrNamed(S.Continue) != null || expr.AttrNamed(GSymbol.Get("continue")) != null)
? BranchMode.ErrorContinue : BranchMode.ErrorExit;
if (expr.Calls(_Error, 1))
expr = expr.Args[0];
else
return DefaultErrorBranch.Value;
} else
mode = BranchMode.None;
return NodeToPred(expr, ctx);
}