public static LNode IfUnless(LNode node, bool isUnless, IMessageSink sink)
{
var args = node.Args;
LNode cond = args.TryGet(0, null), then = args.TryGet(1, null),
elseKW = args.TryGet(2, null), @else = args.TryGet(3, null);
if (cond == null)
{
return(null);
}
if (then == null)
{
return(Reject(sink, cond, "'{0}' statement ended early", isUnless ? "unless" : "if"));
}
if (isUnless)
{
cond = F.Call(S.Not, cond);
}
if (elseKW == null)
{
return(node.With(S.If, cond, then));
}
if (!elseKW.IsIdNamed(_else))
{
return(Reject(sink, elseKW, "'{0}': expected else clause or end-of-statement marker", isUnless ? "unless" : "if"));
}
if (@else.IsId && args.Count > 4)
{
@else = LNode.Call(@else.Name, new VList <LNode>(args.Slice(4)), node);
}
return(node.With(S.If, cond, then, @else));
}
public static LNode @defaultCase(LNode node, IMacroContext context)
{
if (node.ArgCount == 0)
{
return(node.With(S.Label, LNode.Id(S.Default, node)).SetBaseStyle(NodeStyle.Default));
}
else if (node.ArgCount == 1)
{
var arg = node.Args[0];
if (arg.Calls(S.Colon, 1) // .default: {...}
)
{
arg = arg.Args[0];
}
else if (!arg.Calls(S.Braces) // expecting .default {...}
)
{
return(null);
}
return(F.Call(S.Splice,
node.With(S.Label, LNode.Id(S.Default, node)).SetBaseStyle(NodeStyle.Default),
arg));
}
return(null);
}
public static LNode on_finally(LNode node, IMacroContext context)
{
LNode firstArg, rest, on_handler = ValidateOnStmt(node, context, out rest, out firstArg);
if (on_handler == null || firstArg != null)
return null;
return node.With(S.Try, rest, node.With(S.Finally, on_handler));
}
private static LNode TransformOnCatch(LNode node, LNode firstArg, LNode rest, LNode on_handler)
{
if (on_handler == null)
return null;
if (firstArg == null)
firstArg = LNode.Missing;
else if (firstArg.IsId)
firstArg = firstArg.With(S.Var, F.Id(_Exception), firstArg);
return node.With(S.Try, rest, node.With(S.Catch, firstArg, F.Missing, on_handler));
}
public static LNode on_finally(LNode node, IMacroContext context)
{
VList<LNode> rest;
LNode firstArg, on_handler = ValidateOnStmt(node, context, out rest, out firstArg);
if (on_handler == null || firstArg != null)
return null;
node.Style &= ~NodeStyle.OneLiner; // avoid collapsing output to one line
return node.With(S.Try, F.Braces(rest), node.With(S.Finally, on_handler));
}
public static LNode on_finally(LNode node, IMacroContext context)
{
LNode firstArg, rest, on_handler = ValidateOnStmt(node, context, out rest, out firstArg);
if (on_handler == null || firstArg != null)
{
return(null);
}
return(node.With(S.Try, rest, node.With(S.Finally, on_handler)));
}
private static LNode TransformOnCatch(LNode node, LNode firstArg, LNode rest, LNode on_handler)
{
if (on_handler == null)
return null;
if (firstArg == null)
firstArg = LNode.Missing;
else if (firstArg.IsId)
firstArg = firstArg.With(S.Var, F.Id(_Exception), firstArg);
node.Style &= ~NodeStyle.OneLiner; // avoid collapsing output to one line
return node.With(S.Try, rest, node.With(S.Catch, firstArg, F.Missing, on_handler));
}
public static LNode @default1(LNode node, IMessageSink sink)
{
if (node.IsId)
{
return(node.With(S.Label, F.Id(S.Default)));
}
else if (node.ArgCount == 1 && node.Args[0].Calls(S.Braces))
{
return(F.Call(S.Splice, new VList <LNode>(node.With(S.Label, new VList <LNode>(F.Id(S.Default))), node.Args[0])));
}
return(null);
}
public static LNode on_finally(LNode node, IMacroContext context)
{
VList <LNode> rest;
LNode firstArg, on_handler = ValidateOnStmt(node, context, out rest, out firstArg);
if (on_handler == null || firstArg != null)
{
return(null);
}
node.Style &= ~NodeStyle.OneLiner; // avoid collapsing output to one line
return(node.With(S.Try, F.Braces(rest), node.With(S.Finally, on_handler)));
}
public static LNode @do(LNode node, IMessageSink sink)
{
var args = node.Args;
if (node.ArgCount == 2 && args.Last.Calls(_while, 1))
{
return(node.With(S.DoWhile, new VList <LNode>(node.Args[0], node.Args[1].Args[0])));
}
else if (node.ArgCount == 3 && args.TryGet(1, null).IsIdNamed(_while))
{
return(node.With(S.DoWhile, new VList <LNode>(node.Args[0], node.Args[2])));
}
return(null);
}
public static LNode @prop(LNode node, IMessageSink sink)
{
var parts = node.Args;
LNode sig = parts.TryGet(0, null), body = parts.TryGet(1, null), name, retVal = null;
if (parts.Count != 2 || !body.Calls(S.Braces))
{
return(Reject(sink, node, "A property definition must have the form prop(Name, { Body }), or prop(Name::type, { Body })"));
}
if (sig.Calls(S._RightArrow, 2) || sig.Calls(S.ColonColon, 2))
{
name = sig.Args[0];
retVal = sig.Args[1];
}
else
{
name = sig;
retVal = F.Missing;
}
if (!IsComplexId(name))
{
return(Reject(sink, name, "Property name must be a complex identifier"));
}
return(node.With(S.Property, retVal, name, F.Missing, body));
}
public static LNode _set(LNode node, IMacroContext context)
{
var lhs = node.Args[0, LNode.Missing];
var name = lhs.Name;
bool isSnippet = name == _hash_snippet;
if ((isSnippet || name == _hash_set) && node.ArgCount == 2 && lhs.IsId)
{
Symbol newTarget = isSnippet ? _hash_setScopedPropertyQuote : _hash_setScopedProperty;
var stmts = node.Args.Slice(1).Select(key =>
{
LNode value = F.@true;
if (key.Calls(S.Assign, 2))
{
value = key.Args[1];
value = context.PreProcess(value);
key = key.Args[0];
if (isSnippet && value.Calls(S.Braces))
{
value = value.Args.AsLNode(S.Splice);
}
}
if (!key.IsId)
{
context.Write(Severity.Error, key, "Invalid key; expected an identifier.");
}
return((LNode)node.With(newTarget, LNode.Literal(key.Name, key), value));
});
return(F.Call(S.Splice, stmts));
}
return(null);
}
private static LNode TransformOnCatch(LNode node, LNode firstArg, LNode rest, LNode on_handler)
{
if (on_handler == null)
{
return(null);
}
if (firstArg == null)
{
firstArg = LNode.Missing;
}
else if (firstArg.IsId)
{
firstArg = firstArg.With(S.Var, F.Id(_Exception), firstArg);
}
return(node.With(S.Try, rest, node.With(S.Catch, firstArg, F.Missing, on_handler)));
}
public static LNode _set(LNode node, IMacroContext context)
{
var lhs = node.Args[0, LNode.Missing];
var name = lhs.Name;
bool isSnippet = name == _hash_snippet;
if ((isSnippet || name == _hash_set) && node.ArgCount == 2 && lhs.IsId)
{
node = context.PreProcessChildren();
Symbol newTarget = isSnippet ? _hash_setScopedPropertyQuote : _hash_setScopedProperty;
var stmts = node.Args.Slice(1).Select(key =>
{
LNode value = F.@true;
if (key.Calls(S.Assign, 2))
{
value = key.Args[1];
key = key.Args[0];
if (isSnippet && value.Calls(S.Braces))
value = value.Args.AsLNode(S.Splice);
}
if (!key.IsId)
context.Write(Severity.Error, key, "Invalid key; expected an identifier.");
return node.With(newTarget, LNode.Literal(key.Name, key), value);
});
return F.Call(S.Splice, stmts);
}
return null;
}
public sealed override LNode Select(Func <LNode, LNode> selector)
{
LNode result = WithAttrs(n => Maybe.Value(selector(n)));
LNode target = selector(Target);
var args = Args.SmartSelect(selector);
return(result.With(target, args));
}
public static LNode runSequence(LNode node, IMacroContext context)
{
if (context.Parent.Calls(S.Braces))
return node.With(S.Splice, MaybeRemoveNoOpFromRunSeq(node.Args));
if (!context.ScopedProperties.ContainsKey(_useSequenceExpressionsIsRunning))
Reject(context, node, "#useSequenceExpressions is required to make #runSequence work");
return null;
}
public static LNode Do(LNode node, IMacroContext context)
{
if (node.ArgCount == 2 && node.Args[1].Calls(S.While, 1))
{
return(node.With(S.DoWhile, node[0], node[1].Args[0]));
}
return(null);
}
public static LNode @throw(LNode node, IMessageSink sink)
{
if (node.ArgCount > 1)
{
return(null);
}
return(node.With(S.Throw, node.Args)); // change throw -> #throw() and throw(x) -> #throw(x)
}
public static LNode QuestionMark(LNode node, IMessageSink sink)
{
if (node.ArgCount == 2 && node.Args[1].Calls(S.Colon, 2))
{
return(node.With(S.QuestionMark, node.Args[0], node.Args[1].Args[0], node.Args[1].Args[1]));
}
return(null);
}
public static LNode GotoCase(LNode node, IMessageSink sink)
{
if (node.ArgCount == 2 && node.Args[0].IsIdNamed(_case))
{
return(node.With(S.GotoCase, node.Args[1]));
}
return(null);
}
LNode EliminateSequenceExpressionsInChildStmt(LNode stmt)
{
stmt = EliminateSequenceExpressionsInExecStmt(stmt);
if (stmt.Calls(__numrunSequence))
{
return(stmt.With(S.Braces, MaybeRemoveNoOpFromRunSeq(stmt.Args)));
}
return(stmt);
}
private static LNode TransformOnCatch(LNode node, LNode firstArg, LNode rest, LNode on_handler)
{
if (on_handler == null)
{
return(null);
}
if (firstArg == null)
{
firstArg = LNode.Missing;
}
else if (firstArg.IsId)
{
firstArg = firstArg.With(S.Var, F.Id(_Exception), firstArg);
}
node.Style &= ~NodeStyle.OneLiner; // avoid collapsing output to one line
return(node.With(S.Try, rest, node.With(S.Catch, firstArg, F.Missing, on_handler)));
}
public static LNode QuickBind(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2)
{
return(node.With(S.Var, new VList <LNode>(F.Missing, F.Call(S.Assign, a[1], a[0]))));
}
return(null);
}
public static LNode ColonEquals(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2)
{
LNode name = a[0], value = a[1];
return(node.With(S.Var, F.Missing, F.Call(S.Assign, name, value)));
}
return(null);
}
public static LNode ColonColon(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2)
{
var r = node.With(S.Var, a[1], a[0]);
r.BaseStyle = NodeStyle.Operator;
return(r);
}
return(null);
}
public static LNode runSequence(LNode node, IMacroContext context)
{
if (context.Parent.Calls(S.Braces))
{
return(node.With(S.Splice, MaybeRemoveNoOpFromRunSeq(node.Args)));
}
if (!context.ScopedProperties.ContainsKey(_useSequenceExpressionsIsRunning))
{
Reject(context, node, "#useSequenceExpressions is required to make #runSequence work");
}
return(null);
}
public static LNode ColonColonInit(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2)
{
LNode name = a[0], value = a[1];
if (name.Calls(S.ColonColon, 2))
{
return(node.With(S.Var, name.Args[1], F.Call(S.Assign, name.Args[0], value)));
}
}
return(null);
}
public static LNode @for(LNode node, IMessageSink sink)
{
LNode tuple;
if (node.ArgCount == 2 && (tuple = node.Args[0]).Calls(S.Tuple, 3))
{
return(node.With(S.For, tuple.Args[0], tuple.Args[1], tuple.Args[2], node.Args[1]));
}
else if (node.ArgCount == 4)
{
return(node.WithTarget(S.For));
}
return(null);
}
public static LNode @foreach(LNode node, IMessageSink sink)
{
var args = node.Args;
if (args.Count == 2 && args[0].Calls(_in, 2))
{
LNode decl = args[0].Args[0], list = args[0].Args[1], body = args[1];
if (decl.IsId)
{
decl = F.Var(F.Missing, decl);
}
return(node.With(S.ForEach, decl, list, body));
}
return(null);
}
public static LNode rule(LNode node, IMacroContext context)
{
bool isToken;
if ((isToken = node.Calls(_token, 2)) || node.Calls(_rule, 2))
{
node = context.PreProcessChildren();
LNode sig = node.Args[0];
// Ugh. Because the rule has been macro-processed, "rule X::Y ..."
// has become "rule #var(Y,X) ...". We must allow this, because in
// case of something like "rule X(arg::int)::Y" we actually do want
// the argument to become `#var(int, arg)`; so just reverse the
// transform that we didn't want.
if (sig.Calls(S.Var, 2))
{
sig = F.Call(S.ColonColon, sig.Args[1], sig.Args[0]);
}
LNode name = sig, returnType = F.Void;
if (sig.Calls(S.ColonColon, 2))
{
returnType = sig.Args[1];
name = sig.Args[0];
}
if (EcsValidators.IsComplexIdentifier(name))
{
name = F.Call(name); // def requires an argument list
}
LNodeList args = name.Args;
name = name.Target;
LNode newBody = ParseRuleBody(node.Args[1], context);
if (newBody != null)
{
return(node.With(isToken ? _hash_token : _hash_rule,
returnType, name, F.AltList(args), newBody));
}
}
return(null);
}
private static LNode ParseRuleBody(LNode ruleBody, IMessageSink sink)
{
TokenTree ruleTokens;
if ((ruleTokens = ruleBody.Value as TokenTree) == null && !ruleBody.Calls(S.Braces))
{
return(null);
}
if (ruleTokens != null)
{
return(StageOneParser.ParseTokenTree(ruleTokens, sink, ruleBody));
}
else
{
if (ruleBody.Args.Any(stmt => stmt.Value is TokenTree))
{
ruleBody = ruleBody.With(S.Tuple, ruleBody.Args.SmartSelect(stmt => ParseStmtInRule(stmt, sink)));
}
}
return(ruleBody);
}
public static LNode rule(LNode node, IMacroContext context)
{
bool isToken;
if ((isToken = node.Calls(_token, 2)) || node.Calls(_rule, 2))
{
node = context.PreProcessChildren();
LNode sig = node.Args[0];
// Ugh. Because the rule has been macro-processed, "rule X::Y ..."
// has become "rule #var(Y,X) ...". Reverse this transform.
if (sig.Calls(S.Var, 2))
{
sig = F.Call(S.ColonColon, sig.Args[1], sig.Args[0]);
}
LNode name = sig, returnType = F.Void;
if (sig.Calls(S.ColonColon, 2))
{
returnType = sig.Args[1];
name = sig.Args[0];
}
if (LeMP.Prelude.Les.Macros.IsComplexId(name))
{
name = F.Call(name); // def requires an argument list
}
RVList <LNode> args = name.Args;
name = name.Target;
LNode newBody = ParseRuleBody(node.Args[1], context);
if (newBody != null)
{
return(node.With(isToken ? _hash_token : _hash_rule,
returnType, name, F.List(args), newBody));
}
}
return(null);
}
private static LNode ParseRuleBody(LNode ruleBody, IMessageSink sink)
{
TokenTree ruleTokens;
// Expecting @{...} or {...}
if ((ruleTokens = ruleBody.Value as TokenTree) == null && !ruleBody.Calls(S.Braces))
{
sink.Error(ruleBody, "Expected token tree or braced block");
return(null);
}
if (ruleTokens != null)
{
return(StageOneParser.ParseTokenTree(ruleTokens, sink));
}
else
{
if (ruleBody.Args.Any(stmt => stmt.Value is TokenTree))
{
ruleBody = ruleBody.With(S.Tuple, ruleBody.Args.SmartSelect(stmt => ParseStmtInRule(stmt, sink)));
}
}
return(ruleBody);
}
public static LNode VarDecl(LNode node, IMacroContext context)
{
var a = node.Args;
if (a.Count == 2)
{
LNode name = a[0], type = a[1], nameAssignment = name;
if (type.Calls(S.Assign, 2))
{
nameAssignment = type.WithArgs(name, type[1]);
type = type[0];
}
if (name.IsId)
{
return(node.With(S.Var, type, nameAssignment).SetBaseStyle(NodeStyle.Default));
}
else
{
context.Write(Severity.Note, node, "Unrecognized variable declaration syntax");
return(null);
}
}
return(null);
}
public static LNode IfUnless(LNode node, bool isUnless, IMessageSink sink)
{
var args = node.Args;
LNode cond = args.TryGet(0, null), then = args.TryGet(1, null),
elseKW = args.TryGet(2, null), @else = args.TryGet(3, null);
if (cond == null)
return null;
if (then == null)
return Reject(sink, cond, "'{0}' statement ended early", isUnless ? "unless" : "if");
if (isUnless)
cond = F.Call(S.Not, cond);
if (elseKW == null)
return node.With(S.If, cond, then);
if (!elseKW.IsIdNamed(_else))
return Reject(sink, elseKW, "'{0}': expected else clause or end-of-statement marker", isUnless ? "unless" : "if");
if (@else.IsId && args.Count > 4)
@else = LNode.Call(@else.Name, new RVList<LNode>(args.Slice(4)), node);
return node.With(S.If, cond, then, @else);
}
public static LNode unroll(LNode var, LNode cases, LNode body, IMessageSink sink)
{
if (!cases.Calls(S.Tuple) && !cases.Calls(S.Braces))
return Reject(sink, cases, "unroll: the right-hand side of 'in' should be a tuple");
// Maps identifiers => replacements. The integer counts how many times replacement occurred.
var replacements = InternalList<Triplet<Symbol, LNode, int>>.Empty;
if (var.IsId && !var.HasPAttrs()) {
replacements.Add(Pair.Create(var.Name, (LNode)LNode.Missing, 0));
} else {
var vars = var.Args;
if ((var.Calls(S.Tuple) || var.Calls(S.Braces)) && vars.All(a => a.IsId && !a.HasPAttrs())) {
replacements = new Triplet<Symbol, LNode, int>[vars.Count].AsInternalList();
for (int i = 0; i < vars.Count; i++) {
replacements.InternalArray[i].A = vars[i].Name;
// Check for duplicate names
for (int j = 0; j < i; j++)
if (replacements[i].A == replacements[j].A && replacements[i].A.Name != "_")
sink.Write(Severity.Error, vars[i], "unroll: duplicate name in the left-hand tuple"); // non-fatal
}
} else
return Reject(sink, cases, "unroll: the left-hand side of 'in' should be a simple identifier or a tuple of simple identifiers.");
}
UnrollCtx ctx = new UnrollCtx { Replacements = replacements };
WList<LNode> output = new WList<LNode>();
int iteration = 0;
foreach (LNode replacement in cases.Args)
{
iteration++;
bool tuple = replacement.Calls(S.Tuple) || replacement.Calls(S.Braces);
int count = tuple ? replacement.ArgCount : 1;
if (replacements.Count != count)
{
sink.Write(Severity.Error, replacement, "unroll, iteration {0}: Expected {1} replacement items, got {2}", iteration, replacements.Count, count);
if (count < replacements.Count)
continue; // too few
}
for (int i = 0; i < replacements.Count; i++)
replacements.InternalArray[i].B = tuple ? replacement.Args[i] : replacement;
if (body.Calls(S.Braces)) {
foreach (LNode stmt in body.Args)
output.Add(ctx.Replace(stmt).Value);
} else
output.Add(ctx.Replace(body).Value);
}
foreach (var r in replacements)
if (r.C == 0 && !r.A.Name.StartsWith("_"))
sink.Write(Severity.Warning, var, "Replacement variable '{0}' was never used", r.A);
return body.With(S.Splice, output.ToVList());
}
LNode EliminateSequenceExpressionsInChildStmt(LNode stmt)
{
stmt = EliminateSequenceExpressionsInExecStmt(stmt);
if (stmt.Calls(__numrunSequence))
return stmt.With(S.Braces, MaybeRemoveNoOpFromRunSeq(stmt.Args));
return stmt;
}
public static LNode QuickBind(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2)
return node.With(S.Var, new RVList<LNode>(F._Missing, F.Call(S.Assign, a[1], a[0])));
return null;
}
public static LNode ColonColonInit(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2) {
LNode name = a[0], value = a[1];
if (name.Calls(S.ColonColon, 2))
return node.With(S.Var, name.Args[1], F.Call(S.Assign, name.Args[0], value));
}
return null;
}
public static LNode QuestionMark(LNode node, IMessageSink sink)
{
if (node.ArgCount == 2 && node.Args[1].Calls(S.Colon, 2))
return node.With(S.QuestionMark, node.Args[0], node.Args[1].Args[0], node.Args[1].Args[1]);
return null;
}
public static LNode @try(LNode node, IMessageSink sink)
{
if (!node.IsCall)
return null;
// try(code, catch, Exception::e, handler, catch, ..., finally, handler)
// ...becomes...
// #try(#{ stmt1; stmt2; ... }, #catch(#var(Exception, e), handler), #finally(handler))
LNode finallyCode = null;
RWList<LNode> clauses = new RWList<LNode>();
var parts = node.Args;
for (int i = parts.Count-2; i >= 1; i -= 2)
{
var p = parts[i];
if (p.IsIdNamed(_finally)) {
if (clauses.Count != 0 || finallyCode != null)
sink.Write(Severity.Error, p, "The «finally» clause must come last, there can only be one of them.");
finallyCode = parts[i+1];
} else if (p.Name == _catch) {
if (p.ArgCount > 0) {
// This is a normal catch clause
clauses.Insert(0, F.Call(S.Catch, F.Call(S.Splice, p.Args), parts[i + 1]));
} else {
// This is a catch-all clause (the type argument is missing)
if (clauses.Count != 0)
sink.Write(Severity.Error, p, "The catch-all clause must be the last «catch» clause.");
clauses.Add(F.Call(S.Catch, F._Missing, parts[i + 1]));
}
} else if (i > 1 && parts[i-1].IsIdNamed(_catch)) {
// This is a normal catch clause
clauses.Insert(0, F.Call(S.Catch, AutoRemoveParens(p), parts[i+1]));
i--;
} else {
return Reject(sink, p, "Expected «catch» or «finally» clause here. Clause is missing or malformed.");
}
if (i == 2)
return Reject(sink, parts[1], "Expected «catch» or «finally» clause here. Clause is missing or malformed.");
}
if (clauses.Count == 0 && finallyCode == null) {
Debug.Assert(node.ArgCount <= 1);
return Reject(sink, node, "Missing «catch, Type, Code» or «finally, Code» clause");
}
if (finallyCode != null)
clauses.Add(F.Call(S.Finally, finallyCode));
clauses.Insert(0, node.Args[0]);
return node.With(S.Try, clauses.ToRVList());
}
static LNode DefOrConstructor(LNode node, IMessageSink sink, bool isCons)
{
var parts = node.Args;
LNode sig = parts.TryGet(0, null), body = parts.TryGet(1, null);
if (!parts.Count.IsInRange(1, 2) || !sig.IsCall || (body != null && !body.Calls(S.Braces)))
return null;
LNode forwardTo = null, retVal = null;
if (sig.Calls(S.Forward, 2)) {
forwardTo = sig.Args[1];
sig = sig.Args[0];
if (body != null)
return Reject(sink, sig.Target, "Cannot use ==> and a method body {...} at the same time.");
}
if (sig.Calls(S._RightArrow, 2) || sig.Calls(S.ColonColon, 2)) {
retVal = sig.Args[1];
sig = sig.Args[0];
}
if (retVal != null && retVal.Calls(S.Braces) && body == null) {
body = retVal;
retVal = F._Missing;
}
var name = sig.Target ?? sig;
if (!IsTargetDefinitionId(sig, true))
return Reject(sink, sig.Target, "Invalid method name");
var argList = sig.ArgCount != 0 ? sig.WithTarget(S.AltList) : F.List();
if (retVal == null)
retVal = isCons ? F._Missing : F.Void;
else if (isCons)
return Reject(sink, retVal, "A constructor cannot have a return type");
Symbol kind = isCons ? S.Cons : S.Fn;
if (body != null)
return node.With(kind, retVal, name, argList, body);
else if (forwardTo != null)
return node.With(kind, retVal, name, argList, F.Call(S.Forward, forwardTo));
else
return node.With(kind, retVal, name, argList);
}
public static LNode TranslateSpaceDefinition(LNode node, IMacroContext context, Symbol newTarget)
{
if (!node.IsCall)
return null;
bool isAlias = newTarget == S.Alias, isNamespace = newTarget == S.Namespace;
var args = node.Args;
LNode nameEtc = args.TryGet(0, null), body = args.TryGet(1, null), oldName = null;
if (args.Count == 1 ? !isAlias : (args.Count != 2 || !body.Calls(S.Braces))) {
if (isNamespace && args.Count == 1) {
// Special case: a namespace can auto-wrap whatever statements follow.
body = F.Braces(context.RemainingNodes);
context.DropRemainingNodes = true;
} else
return Reject(context, node, "A type definition must have the form kind(Name, { Body }) or kind(Name(Bases), { Body }) (where «kind» is struct/class/enum/trait/alias)");
}
if (isAlias) {
if (!nameEtc.Calls(S.Assign, 2))
return Reject(context, node, "An 'alias' (or 'using') definition must have the form alias(NewName = OldName, { Body }) or alias(NewName(Interfaces) = OldName, { Body })");
oldName = nameEtc.Args[1];
nameEtc = nameEtc.Args[0];
}
LNode name, bases;
if (IsComplexId(nameEtc, true)) {
name = nameEtc;
bases = F.List();
} else {
name = nameEtc.Target ?? nameEtc;
bases = nameEtc.WithTarget(S.AltList);
}
if (isNamespace) {
if (!IsComplexId(name, true))
return Reject(context, name, "Invalid namespace name (expected a complex identifier)");
} else {
if (!IsDefinitionId(name, false))
return Reject(context, name, "Invalid type name (expected a simple name or Name!(T1,T2,...))");
}
if (isAlias) {
if (body == null)
return node.With(newTarget, F.Call(S.Assign, name, oldName), bases);
else
return node.With(newTarget, F.Call(S.Assign, name, oldName), bases, body);
} else {
Debug.Assert(body != null);
return node.With(newTarget, name, bases, body);
}
}
public static LNode import_macros(LNode node, IMacroContext sink)
{
return node.With(_importMacros, node.Args);
}
public static LNode @for(LNode node, IMessageSink sink)
{
LNode tuple;
if (node.ArgCount == 2 && ((tuple = node.Args[0]).Calls(S.Tuple, 3) || tuple.Calls(S.Tuple, 2)))
return node.With(S.For,
asAltList(tuple.Args[0]),
tuple.Args[1],
asAltList(tuple.Args[2, LNode.Missing]),
node.Args[1]);
else if (node.ArgCount == 4)
return node.With(S.For,
asAltList(node.Args[0]),
node.Args[1],
asAltList(node.Args[2]),
node.Args[3]);
return null;
}
public static LNode ColonColon(LNode node, IMessageSink context)
{
var a = node.Args;
if (a.Count == 2) {
if (a[0].IsId) {
var r = node.With(S.Var, a[1], a[0]);
r.BaseStyle = NodeStyle.Operator;
return r;
} else if (a[0].CallsMin(S.Tuple, 1)) {
var r = node.With(S.Var, new VList<LNode>(a[1]).AddRange(a[0].Args));
r.BaseStyle = NodeStyle.Operator;
return r;
} else
return Reject(context, node, "Expected a variable name or tuple to the left of `::`");
}
return null;
}
public static LNode @default1(LNode node, IMessageSink sink)
{
if (node.IsId)
return node.With(S.Label, F.Id(S.Default));
else if (node.ArgCount == 1 && node.Args[0].Calls(S.Braces))
return F.Call(S.Splice, new RVList<LNode>(node.With(S.Label, new RVList<LNode>(F.Id(S.Default))), node.Args[0]));
return null;
}
public static LNode @prop(LNode node, IMessageSink sink)
{
var parts = node.Args;
LNode sig = parts.TryGet(0, null), body = parts.TryGet(1, null), name, retVal = null;
if (parts.Count != 2 || !body.Calls(S.Braces))
return Reject(sink, node, "A property definition must have the form prop(Name, { Body }), or prop(Name::type, { Body })");
if (sig.Calls(S._RightArrow, 2) || sig.Calls(S.ColonColon, 2)) {
name = sig.Args[0];
retVal = sig.Args[1];
} else {
name = sig;
retVal = F._Missing;
}
if (!IsComplexId(name))
return Reject(sink, name, "Property name must be a complex identifier");
return node.With(S.Property, retVal, name, body);
}
public static LNode GotoCase(LNode node, IMessageSink sink)
{
if (node.ArgCount == 2 && node.Args[0].IsIdNamed(_case))
return node.With(S.GotoCase, node.Args[1]);
return null;
}
public static LNode @var(LNode node, IMessageSink sink)
{
var parts = node.Args;
if (parts.Count == 0)
return Reject(sink, node, "A variable definition must have the form var(Name::Type), var(Name = value), or var(Name::Type = value)");
if (parts[0].IsId)
return null; // e.g. this is true for "static readonly x::Foo"
RWList<LNode> varStmts = null;
LNode varStmt = null;
for (int i = 0; i < parts.Count; i++) {
LNode part = parts[i], type = null, init = null;
if (part.Calls(S.Assign, 2)) {
init = part.Args[1];
part = part.Args[0];
}
if (part.Calls(S.ColonColon, 2)) {
type = part.Args[1];
part = part.Args[0];
}
if (init == null && part.Calls(S.Assign, 2)) {
init = part.Args[1];
part = part.Args[0];
}
if (!part.IsId)
return Reject(sink, part, "Expected a simple variable name here");
if (type != null && !IsComplexId(type))
return Reject(sink, type, "Expected a type name here");
type = type ?? F._Missing;
var nameAndInit = init == null ? part : F.Call(S.Assign, part, init);
if (varStmt != null && varStmt.Args[0].Equals(type)) {
// same type used again, e.g. (var x::int y::int) => (#var int x y)
varStmt = varStmt.WithArgs(varStmt.Args.Add(nameAndInit));
} else {
// first item (var x::int => #var int x) or type changed (var a::A b::B => #var A a; #var B b)
if (varStmt != null) {
varStmts = varStmts ?? new RWList<LNode>();
varStmts.Add(varStmt);
}
varStmt = node.With(S.Var, type, nameAndInit);
}
}
// Return a single statement or a list of them if necessary
if (varStmts != null) {
varStmts.Add(varStmt);
return F.Call(S.Splice, varStmts.ToRVList());
} else {
return varStmt;
}
}
public static LNode @throw(LNode node, IMessageSink sink)
{
if (node.ArgCount > 1) return null;
return node.With(S.Throw, node.Args); // change throw -> #throw() and throw(x) -> #throw(x)
}
public static LNode import_macros(LNode node, IMessageSink sink)
{
return node.With(_importMacros, node.Args);
}
public static LNode ColonColon(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2) {
var r = node.With(S.Var, a[1], a[0]);
r.BaseStyle = NodeStyle.Operator;
return r;
}
return null;
}
public static LNode @for(LNode node, IMessageSink sink)
{
LNode tuple;
if (node.ArgCount == 2 && (tuple = node.Args[0]).Calls(S.Tuple, 3))
return node.With(S.For, tuple.Args[0], tuple.Args[1], tuple.Args[2], node.Args[1]);
else if (node.ArgCount == 4)
return node.WithTarget(S.For);
return null;
}
public static LNode ColonEquals(LNode node, IMessageSink sink)
{
var a = node.Args;
if (a.Count == 2) {
LNode name = a[0], value = a[1];
return node.With(S.Var, F._Missing, F.Call(S.Assign, name, value));
}
return null;
}
public static LNode @foreach(LNode node, IMessageSink sink)
{
var args = node.Args;
if (args.Count == 2 && args[0].Calls(_in, 2)) {
LNode decl = args[0].Args[0], list = args[0].Args[1], body = args[1];
if (decl.IsId)
decl = F.Var(F._Missing, decl);
return node.With(S.ForEach, decl, list, body);
}
return null;
}
private void InjectTriviaInChildren(LNode parent, out SourceRange triviaRange, out Maybe <Trivia> trivia, int indexInParent, ref LNode node)
{
// Current trivia's range is within node's range: Apply it to
// the node's children, if any. First gather list of children
// and sort by source-code order, if necessary:
int min = node.Min;
InternalList <Pair <LNode, int> > children = InternalList <Pair <LNode, int> > .Empty;
children.Resize(node.Max - min + 1);
bool inOrder = true;
int start, prevStart = int.MinValue;
for (int i = 0; i < children.Count; i++, prevStart = start)
{
children[i] = Pair.Create(node[i + min], i + min);
start = children[i].A.Range.StartIndex;
if (prevStart > start)
{
inOrder = false;
}
}
if (!inOrder)
{
children.Sort((a, b) => a.Item1.Range.StartIndex.CompareTo(b.Item1.Range.StartIndex));
}
// Call ourself recursively to apply trivia to children. Usually,
// newChildren is the same length as children, but it may have extra
// trivia attributes added.
InternalList <Pair <LNode, int> > newChildren = new InternalList <Pair <LNode, int> >(children.Count);
var output = RunCore(children.GetEnumerator(), node);
bool changed = false;
while (output.MoveNext())
{
var @new = output.Current;
newChildren.Add(@new);
if (@new.Item1 != children[@new.Item2 - min].Item1)
{
changed = true;
}
}
// At the end, gather up any remaining trivia
InternalList <Trivia> triviaList = InternalList <Trivia> .Empty;
trivia = CurrentTrivia(out triviaRange);
while (trivia.HasValue && triviaRange.EndIndex <= node.Range.EndIndex)
{
triviaList.Add(trivia.Value);
trivia = AdvanceTrivia(out triviaRange);
changed = true;
}
if (changed)
{
// If this is a call, attach any remaining trivia to the last child.
if (node.IsCall && !triviaList.IsEmpty)
{
int i = newChildren.Count - 1;
var last = newChildren.InternalArray[i];
newChildren.InternalArray[i].A = AttachTriviaTo(last.A, triviaList, TriviaLocation.TrailingExtra, node, last.B) ?? last.A;
}
// Put the children back in their "conceptual" order
if (!inOrder)
{
newChildren.StableSort((a, b) => a.Item2.CompareTo(b.Item2));
}
// Update node's attributes, if any
int numAttrs = newChildren.TakeWhile(p => p.B < -1).Count();
if (numAttrs > 0)
{
var attrs = LNode.List(newChildren.Slice(0, numAttrs).SelectArray(p => p.A));
node = node.WithAttrs(attrs);
}
if (node.IsCall)
{
Debug.Assert(newChildren[numAttrs].B == -1);
var newArgs = newChildren.Slice(numAttrs + 1).SelectArray(p => p.A);
node = node.With(newChildren[numAttrs].A, LNode.List(newArgs));
}
else if (!triviaList.IsEmpty)
{
// If current node is not a call, attach any remaining trivia to it.
node = AttachTriviaTo(node, triviaList, TriviaLocation.Ambiguous, parent, indexInParent);
}
}
}
public static LNode @do(LNode node, IMessageSink sink)
{
var args = node.Args;
if (node.ArgCount == 2 && args.Last.Calls(_while, 1)) {
return node.With(S.DoWhile, new RVList<LNode>(node.Args[0], node.Args[1].Args[0]));
} else if (node.ArgCount == 3 && args.TryGet(1, null).IsIdNamed(_while)) {
return node.With(S.DoWhile, new RVList<LNode>(node.Args[0], node.Args[2]));
}
return null;
}
public static LNode unroll(LNode var, VList <LNode> cases, LNode body, IMessageSink sink)
{
// Maps identifiers => replacements. The integer counts how many times replacement occurred.
var replacements = InternalList <Triplet <Symbol, LNode, int> > .Empty;
if (var.IsId && !var.HasPAttrs())
{
replacements.Add(Pair.Create(var.Name, (LNode)LNode.Missing, 0));
}
else
{
var vars = var.Args;
if ((var.Calls(S.Tuple) || var.Calls(S.Braces)) && vars.All(a => a.IsId && !a.HasPAttrs()))
{
replacements = new Triplet <Symbol, LNode, int> [vars.Count].AsInternalList();
for (int i = 0; i < vars.Count; i++)
{
replacements.InternalArray[i].A = vars[i].Name;
// Check for duplicate names
for (int j = 0; j < i; j++)
{
if (replacements[i].A == replacements[j].A && replacements[i].A.Name != "_")
{
sink.Error(vars[i], "Duplicate name in the left-hand tuple"); // non-fatal
}
}
}
}
else
{
return(Reject(sink, var, "The left-hand side of 'in' should be a simple identifier or a tuple of simple identifiers."));
}
}
UnrollCtx ctx = new UnrollCtx {
Replacements = replacements
};
WList <LNode> output = new WList <LNode>();
int iteration = 0;
foreach (LNode replacement in cases)
{
iteration++;
bool tuple = replacement.Calls(S.Tuple) || replacement.Calls(S.Braces);
int count = tuple ? replacement.ArgCount : 1;
if (replacements.Count != count)
{
sink.Error(replacement, "iteration {0}: Expected {1} replacement items, got {2}", iteration, replacements.Count, count);
if (count < replacements.Count)
{
continue; // too few
}
}
for (int i = 0; i < replacements.Count; i++)
{
replacements.InternalArray[i].B = tuple ? replacement.Args[i] : replacement;
}
if (body.Calls(S.Braces))
{
foreach (LNode stmt in body.Args)
{
output.Add(ctx.Replace(stmt).Value);
}
}
else
{
output.Add(ctx.Replace(body).Value);
}
}
foreach (var r in replacements)
{
if (r.C == 0 && !r.A.Name.StartsWith("_"))
{
sink.Write(Severity.Warning, var, "Replacement variable '{0}' was never used", r.A);
}
}
return(body.With(S.Splice, output.ToVList()));
}
public static LNode @unless(LNode node, IMessageSink sink)
{
var args = node.Args;
LNode cond = args.TryGet(0, null), then = args.TryGet(1, null), @else = args.TryGet(3, null);
if (node.ArgCount != 2 && (node.ArgCount != 4 || !args.TryGet(2, null).IsIdNamed(_else)))
return Reject(sink, node, "An unless-statement must have the form «unless(Cond, expr)» or «unless(Cond, ThenClause, else, ElseClause)»");
if (@else == null)
return node.With(S.If, F.Call(S.Not, cond), then);
else
return node.With(S.If, F.Call(S.Not, cond), then, @else);
}