protected override Expression VisitIteratorExpression(IteratorExpression iex)
{
var context = Arg <BindingContext>(CompilationContext.BindingContext);
var template = FunctionBuilder.CompileCore(new[] { iex.Template }, CompilationContext.Configuration);
var ifEmpty = FunctionBuilder.CompileCore(new[] { iex.IfEmpty }, CompilationContext.Configuration);
if (iex.Sequence is PathExpression pathExpression)
{
pathExpression.Context = PathExpression.ResolutionContext.Parameter;
}
var compiledSequence = Arg <object>(FunctionBuilder.Reduce(iex.Sequence, CompilationContext));
var blockParamsValues = CreateBlockParams();
return(Call(() =>
Iterator.Iterate(context, blockParamsValues, compiledSequence, template, ifEmpty)
));
ExpressionContainer <ChainSegment[]> CreateBlockParams()
{
var parameters = iex.BlockParams?.BlockParam?.Parameters;
if (parameters == null)
{
parameters = ArrayEx.Empty <ChainSegment>();
}
return(Arg(parameters));
}
}
protected override Expression VisitIteratorExpression(IteratorExpression iex)
{
var context = ExpressionShortcuts.Arg <BindingContext>(CompilationContext.BindingContext);
var sequence = ExpressionShortcuts.Var <object>("sequence");
var template = FunctionBuilder.CompileCore(new[] { iex.Template }, CompilationContext.Configuration);
var ifEmpty = FunctionBuilder.CompileCore(new[] { iex.IfEmpty }, CompilationContext.Configuration);
var compiledSequence = ExpressionShortcuts.Arg <object>(FunctionBuilder.Reduce(iex.Sequence, CompilationContext));
var blockParams = ExpressionShortcuts.Arg <BlockParam>(iex.BlockParams);
var blockParamsProvider = ExpressionShortcuts.Call(() => BlockParamsValueProvider.Create(context, blockParams));
var blockParamsProviderVar = ExpressionShortcuts.Var <BlockParamsValueProvider>();
return(ExpressionShortcuts.Block()
.Parameter(sequence, compiledSequence)
.Parameter(blockParamsProviderVar, blockParamsProvider)
.Line(blockParamsProviderVar.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(() =>
Iterator.Iterate(context, self, sequence, template, ifEmpty)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
protected override Expression VisitPartialExpression(PartialExpression pex)
{
var bindingContext = ExpressionShortcuts.Arg <BindingContext>(CompilationContext.BindingContext);
var partialBlockTemplate = pex.Fallback != null
? FunctionBuilder.CompileCore(new[] { pex.Fallback }, CompilationContext.Configuration)
: null;
if (pex.Argument != null || partialBlockTemplate != null)
{
var value = ExpressionShortcuts.Arg <object>(FunctionBuilder.Reduce(pex.Argument, CompilationContext));
var partialTemplate = ExpressionShortcuts.Arg(partialBlockTemplate);
bindingContext = bindingContext.Call(o => o.CreateChildContext(value, partialTemplate));
}
var partialName = ExpressionShortcuts.Cast <string>(pex.PartialName);
var configuration = ExpressionShortcuts.Arg(CompilationContext.Configuration);
return(ExpressionShortcuts.Call(() =>
InvokePartialWithFallback(partialName, bindingContext, (ICompiledHandlebarsConfiguration)configuration)
));
}
protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var context = ExpressionShortcuts.Arg <BindingContext>(CompilationContext.BindingContext);
var bindingContext = isInlinePartial
? context.Cast <object>()
: context.Property(o => o.Value);
var readerContext = ExpressionShortcuts.Arg(bhex.Context);
var body = FunctionBuilder.CompileCore(((BlockExpression)bhex.Body).Expressions, CompilationContext.Configuration);
var inverse = FunctionBuilder.CompileCore(((BlockExpression)bhex.Inversion).Expressions, CompilationContext.Configuration);
var helperName = bhex.HelperName.TrimStart('#', '^');
var textWriter = context.Property(o => o.TextWriter);
var arguments = ExpressionShortcuts.Array <object>(bhex.Arguments.Select(o => FunctionBuilder.Reduce(o, CompilationContext)));
var configuration = ExpressionShortcuts.Arg(CompilationContext.Configuration);
var reducerNew = ExpressionShortcuts.New(() => new LambdaReducer(context, body, inverse));
var reducer = ExpressionShortcuts.Var <LambdaReducer>();
var blockParamsProvider = ExpressionShortcuts.Var <BlockParamsValueProvider>();
var blockParamsExpression = ExpressionShortcuts.Call(
() => BlockParamsValueProvider.Create(context, ExpressionShortcuts.Arg <BlockParam>(bhex.BlockParams))
);
var helperOptions = ExpressionShortcuts.New(
() => new HelperOptions(
reducer.Property(o => o.Direct),
reducer.Property(o => o.Inverse),
blockParamsProvider,
configuration)
);
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(helperName, out var helper))
{
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => helper(textWriter, helperOptions, bindingContext, arguments)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
foreach (var resolver in CompilationContext.Configuration.HelperResolvers)
{
if (resolver.TryResolveBlockHelper(helperName, out helper))
{
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => helper(textWriter, helperOptions, bindingContext, arguments)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
}
var helperPrefix = bhex.HelperName[0];
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => LateBoundCall(
helperName,
helperPrefix,
context,
(IReaderContext)readerContext,
textWriter, helperOptions,
body,
inverse,
bindingContext,
self,
arguments
)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
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)
});