[c] if (conditionWithTemporaries).

fusionlanguage#26, fusionlanguage#140

Author: pfusik

GenBase.fu

@@ -1650,10 +1650,15 @@ public abstract class GenBase : FuVisitor
 		WriteChar(')');
 	}
 
-	void WriteIf!(FuIf statement)
+	protected virtual void StartIf!(FuExpr expr)
 	{
 		Write("if (");
-		StartIfWhile(statement.Cond);
+		StartIfWhile(expr);
+	}
+
+	void WriteIf!(FuIf statement)
+	{
+		StartIf(statement.Cond);
 		WriteChild(statement.OnTrue);
 		if (statement.OnFalse != null) {
 			Write("else");

GenC.fu

@@ -2881,6 +2881,20 @@ public class GenC : GenCCpp
 			NotSupported(statement.Collection, statement.Collection.Type.ToString());
 	}
 
+	protected override void StartIf!(FuExpr expr)
+	{
+		WriteCTemporaries(expr);
+		if (this.CurrentTemporaries.Any(temp => !(temp is FuType))) {
+			Write("bool fucondition = "); // FIXME: already in scope
+			expr.Accept(this, FuPriority.Argument);
+			WriteCharLine(';');
+			CleanupTemporaries();
+			Write("if (fucondition)");
+		}
+		else
+			base.StartIf(expr);
+	}
+
 	internal override void VisitLock!(FuLock statement)
 	{
 		Write("mtx_lock(&");

libfut.cpp

@@ -8026,10 +8026,15 @@ void GenBase::startIfWhile(const FuExpr * expr)
 	writeChar(')');
 }
 
-void GenBase::writeIf(const FuIf * statement)
+void GenBase::startIf(const FuExpr * expr)
 {
 	write("if (");
-	startIfWhile(statement->cond.get());
+	startIfWhile(expr);
+}
+
+void GenBase::writeIf(const FuIf * statement)
+{
+	startIf(statement->cond.get());
 	writeChild(statement->onTrue.get());
 	if (statement->onFalse != nullptr) {
 		write("else");
@@ -11797,6 +11802,20 @@ void GenC::visitForeach(const FuForeach * statement)
 		notSupported(statement->collection.get(), statement->collection->type->toString());
 }
 
+void GenC::startIf(const FuExpr * expr)
+{
+	writeCTemporaries(expr);
+	if (std::any_of(this->currentTemporaries.begin(), this->currentTemporaries.end(), [](const FuExpr * temp) { return !dynamic_cast<const FuType *>(temp); })) {
+		write("bool fucondition = ");
+		expr->accept(this, FuPriority::argument);
+		writeCharLine(';');
+		cleanupTemporaries();
+		write("if (fucondition)");
+	}
+	else
+		GenBase::startIf(expr);
+}
+
 void GenC::visitLock(const FuLock * statement)
 {
 	write("mtx_lock(&");

libfut.cs

@@ -8215,10 +8215,15 @@ void StartIfWhile(FuExpr expr)
 			WriteChar(')');
 		}
 
-		void WriteIf(FuIf statement)
+		protected virtual void StartIf(FuExpr expr)
 		{
 			Write("if (");
-			StartIfWhile(statement.Cond);
+			StartIfWhile(expr);
+		}
+
+		void WriteIf(FuIf statement)
+		{
+			StartIf(statement.Cond);
 			WriteChild(statement.OnTrue);
 			if (statement.OnFalse != null) {
 				Write("else");
@@ -12069,6 +12074,20 @@ internal override void VisitForeach(FuForeach statement)
 				NotSupported(statement.Collection, statement.Collection.Type.ToString());
 		}
 
+		protected override void StartIf(FuExpr expr)
+		{
+			WriteCTemporaries(expr);
+			if (this.CurrentTemporaries.Exists(temp => !(temp is FuType))) {
+				Write("bool fucondition = ");
+				expr.Accept(this, FuPriority.Argument);
+				WriteCharLine(';');
+				CleanupTemporaries();
+				Write("if (fucondition)");
+			}
+			else
+				base.StartIf(expr);
+		}
+
 		internal override void VisitLock(FuLock statement)
 		{
 			Write("mtx_lock(&");

libfut.hpp

@@ -1857,6 +1857,7 @@ class GenBase : public FuVisitor
 	virtual void writeChild(FuStatement * statement);
 	virtual void startBreakGoto();
 	virtual bool embedIfWhileIsVar(const FuExpr * expr, bool write);
+	virtual void startIf(const FuExpr * expr);
 	void defineVar(const FuExpr * value);
 	virtual void writeSwitchCaseTypeVar(const FuExpr * value);
 	virtual void writeSwitchValue(const FuExpr * expr);
@@ -2080,6 +2081,7 @@ class GenC : public GenCCpp
 	void writeIndexingExpr(const FuBinaryExpr * expr, FuPriority parent) override;
 	void writeResource(std::string_view name, int length) override;
 	void cleanupBlock(const FuBlock * statement) override;
+	void startIf(const FuExpr * expr) override;
 	void writeSwitchCaseBody(const std::vector<std::shared_ptr<FuStatement>> * statements) override;
 	void writeStatements(const std::vector<std::shared_ptr<FuStatement>> * statements) override;
 	void writeEnum(const FuEnum * enu) override;

libfut.js

@@ -8537,10 +8537,15 @@ export class GenBase extends FuVisitor
 		this.writeChar(41);
 	}
 
-	#writeIf(statement)
+	startIf(expr)
 	{
 		this.write("if (");
-		this.#startIfWhile(statement.cond);
+		this.#startIfWhile(expr);
+	}
+
+	#writeIf(statement)
+	{
+		this.startIf(statement.cond);
 		this.writeChild(statement.onTrue);
 		if (statement.onFalse != null) {
 			this.write("else");
@@ -12465,6 +12470,20 @@ export class GenC extends GenCCpp
 			this.notSupported(statement.collection, statement.collection.type.toString());
 	}
 
+	startIf(expr)
+	{
+		this.#writeCTemporaries(expr);
+		if (this.currentTemporaries.some(temp => !(temp instanceof FuType))) {
+			this.write("bool fucondition = ");
+			expr.accept(this, FuPriority.ARGUMENT);
+			this.writeCharLine(59);
+			this.cleanupTemporaries();
+			this.write("if (fucondition)");
+		}
+		else
+			super.startIf(expr);
+	}
+
 	visitLock(statement)
 	{
 		this.write("mtx_lock(&");

test/JsonElement.fu

@@ -352,8 +352,7 @@ public static class Test
 {
 	public static bool Run()
 	{
-		JsonElement# json; //FAIL: c leak TODO; cl
-		json = JsonElement.Parse("\"foo\"");
+		JsonElement# json = JsonElement.Parse("\"foo\""); //FAIL: cl
 		if (!json.IsString() || json.GetString() != "foo")
 			return false;
 		json = JsonElement.Parse("10.5");