protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var pathInfo = PathInfoStore.Current.GetOrAdd(bhex.HelperName);
var bindingContext = CompilationContext.Args.BindingContext;
var context = isInlinePartial
? bindingContext.As <object>()
: bindingContext.Property(o => o.Value);
var readerContext = bhex.Context;
var direct = Compile(bhex.Body);
var inverse = Compile(bhex.Inversion);
var args = FunctionBinderHelpers.CreateArguments(bhex.Arguments, CompilationContext);
var direction = bhex.IsRaw || pathInfo.IsBlockHelper ? BlockHelperDirection.Direct : BlockHelperDirection.Inverse;
var blockParams = CreateBlockParams();
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(pathInfo, out var descriptor))
{
return(BindByRef(pathInfo, descriptor));
}
var helperResolvers = CompilationContext.Configuration.HelperResolvers;
for (var index = 0; index < helperResolvers.Count; index++)
{
var resolver = helperResolvers[index];
if (!resolver.TryResolveBlockHelper(pathInfo, out var resolvedDescriptor))
{
continue;
}
descriptor = new Ref <IHelperDescriptor <BlockHelperOptions> >(resolvedDescriptor);
blockHelpers.AddOrReplace(pathInfo, descriptor);
return(BindByRef(pathInfo, descriptor));
}
var lateBindBlockHelperDescriptor = new LateBindBlockHelperDescriptor(pathInfo);
var lateBindBlockHelperRef = new Ref <IHelperDescriptor <BlockHelperOptions> >(lateBindBlockHelperDescriptor);
blockHelpers.AddOrReplace(pathInfo, lateBindBlockHelperRef);
return(BindByRef(pathInfo, lateBindBlockHelperRef));
ExpressionContainer <ChainSegment[]> CreateBlockParams()
{
var parameters = bhex.BlockParams?.BlockParam?.Parameters;
parameters ??= ArrayEx.Empty <ChainSegment>();
return(Arg(parameters));
}
TemplateDelegate Compile(Expression expression)
{
var blockExpression = (BlockExpression)expression;
return(FunctionBuilder.Compile(blockExpression.Expressions, new CompilationContext(CompilationContext)));
}
Expression BindByRef(PathInfo name, Ref <IHelperDescriptor <BlockHelperOptions> > helperBox)
{
var writer = CompilationContext.Args.EncodedWriter;
var helperOptions = direction switch
{
BlockHelperDirection.Direct => New(() => new BlockHelperOptions(name, direct, inverse, blockParams, bindingContext)),
BlockHelperDirection.Inverse => New(() => new BlockHelperOptions(name, inverse, direct, blockParams, bindingContext)),
_ => throw new HandlebarsCompilerException("Helper referenced with unknown prefix", readerContext)
};
var callContext = New(() => new Context(bindingContext, context));
return(Call(() => helperBox.Value.Invoke(writer, helperOptions, callContext, args)));
}
}
}
protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var pathInfo = CompilationContext.Configuration.PathInfoStore.GetOrAdd(bhex.HelperName);
var bindingContext = Arg <BindingContext>(CompilationContext.BindingContext);
var context = isInlinePartial
? bindingContext.As <object>()
: bindingContext.Property(o => o.Value);
var readerContext = bhex.Context;
var direct = Compile(bhex.Body);
var inverse = Compile(bhex.Inversion);
var arguments = CreateArguments();
var helperName = pathInfo.TrimmedPath;
var direction = bhex.IsRaw || pathInfo.IsBlockHelper ? BlockHelperDirection.Direct : BlockHelperDirection.Inverse;
var blockParams = CreateBlockParams();
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(pathInfo, out var descriptor))
{
return(BindByRef(descriptor));
}
var helperResolvers = CompilationContext.Configuration.HelperResolvers;
for (var index = 0; index < helperResolvers.Count; index++)
{
var resolver = helperResolvers[index];
if (!resolver.TryResolveBlockHelper(helperName, out var resolvedDescriptor))
{
continue;
}
return(Bind(resolvedDescriptor));
}
var lateBindBlockHelperDescriptor = new LateBindBlockHelperDescriptor(pathInfo, CompilationContext.Configuration);
var lateBindBlockHelperRef = new StrongBox <BlockHelperDescriptorBase>(lateBindBlockHelperDescriptor);
blockHelpers.Add(pathInfo, lateBindBlockHelperRef);
return(BindByRef(lateBindBlockHelperRef));
ExpressionContainer <ChainSegment[]> CreateBlockParams()
{
var parameters = bhex.BlockParams?.BlockParam?.Parameters;
if (parameters == null)
{
parameters = ArrayEx.Empty <ChainSegment>();
}
return(Arg(parameters));
}
ExpressionContainer <object[]> CreateArguments()
{
var args = bhex.Arguments
.ApplyOn((PathExpression pex) => pex.Context = PathExpression.ResolutionContext.Parameter)
.Select(o => FunctionBuilder.Reduce(o, CompilationContext));
return(Array <object>(args));
}
Action <BindingContext, TextWriter, object> Compile(Expression expression)
{
var blockExpression = (BlockExpression)expression;
return(FunctionBuilder.CompileCore(blockExpression.Expressions, CompilationContext.Configuration));
}
Expression BindByRef(StrongBox <BlockHelperDescriptorBase> value)
{
return(direction switch
{
BlockHelperDirection.Direct => Call(() =>
BlockHelperCallBindingByRef(bindingContext, context, blockParams, direct, inverse, arguments, value)),
BlockHelperDirection.Inverse => Call(() =>
BlockHelperCallBindingByRef(bindingContext, context, blockParams, inverse, direct, arguments, value)),
_ => throw new HandlebarsCompilerException("Helper referenced with unknown prefix", readerContext)
});
