public object let(TemplateScopeContext scope, object target, object scopeBindings) //from filter
{
var objs = target as IEnumerable;
if (objs != null)
{
var scopedParams = scope.GetParamsWithItemBindingOnly(nameof(let), null, scopeBindings, out string itemBinding);
var to = new List <ScopeVars>();
var i = 0;
foreach (var item in objs)
{
scope.ScopedParams[TemplateConstants.Index] = i++;
scope.ScopedParams[itemBinding] = item;
// Copy over previous let bindings into new let bindings
var itemBindings = new ScopeVars();
if (item is object[] tuple)
{
foreach (var a in tuple)
{
if (a is IDictionary <string, object> aArgs)
{
foreach (var entry in aArgs)
{
itemBindings[entry.Key] = entry.Value;
}
}
}
}
foreach (var entry in scopedParams)
{
var bindTo = entry.Key;
if (!(entry.Value is string bindToLiteral))
{
throw new NotSupportedException($"'{nameof(let)}' in '{scope.Page.VirtualPath}' expects a string Expression for its value but received '{entry.Value}' instead");
}
bindToLiteral.ToStringSegment().ParseNextToken(out object value, out JsBinding binding);
var bindValue = scope.Evaluate(value, binding);
scope.ScopedParams[bindTo] = bindValue;
itemBindings[bindTo] = bindValue;
}
to.Add(itemBindings);
}
return(to);
}
if (target != null)
{
throw new NotSupportedException($"'{nameof(let)}' in '{scope.Page.VirtualPath}' requires an IEnumerable but received a '{target.GetType()?.Name}' instead");
}
return(null);
}
public object let(TemplateScopeContext scope, object target, object scopeBindings) //from filter
{
if (target is IEnumerable objs)
{
string itemBinding;
Dictionary <string, object> scopedParams = null;
var arrowExpr = scopeBindings as JsArrowFunctionExpression;
if (arrowExpr != null)
{
itemBinding = arrowExpr.Params[0].Name;
}
else
{
scopedParams = scope.GetParamsWithItemBindingOnly(nameof(@let), null, scopeBindings, out itemBinding);
}
var to = new List <ScopeVars>();
var i = 0;
foreach (var item in objs)
{
scope.ScopedParams[TemplateConstants.Index] = i++;
scope.ScopedParams[itemBinding] = item;
// Copy over previous let bindings into new let bindings
var itemBindings = new ScopeVars();
if (item is object[] tuple)
{
foreach (var a in tuple)
{
if (a is IDictionary <string, object> aArgs)
{
foreach (var entry in aArgs)
{
itemBindings[entry.Key] = entry.Value;
}
}
}
}
if (arrowExpr != null)
{
var value = arrowExpr.Body.Evaluate(scope);
if (value is Dictionary <string, object> bindingVars)
{
foreach (var bindingVar in bindingVars)
{
itemBindings[bindingVar.Key] = bindingVar.Value;
}
}
}
else
{
foreach (var entry in scopedParams)
{
var bindTo = entry.Key;
if (!(entry.Value is string bindToLiteral))
{
throw new NotSupportedException($"'{nameof(let)}' in '{scope.Page.VirtualPath}' expects a string Expression for its value but received '{entry.Value}' instead");
}
bindToLiteral.ParseJsExpression(out JsToken token);
var bindValue = token.Evaluate(scope);
scope.ScopedParams[bindTo] = bindValue;
itemBindings[bindTo] = bindValue;
}
}
to.Add(itemBindings);
}
return(to);
}
if (target != null)
{
throw new NotSupportedException($"'{nameof(let)}' in '{scope.Page.VirtualPath}' requires an IEnumerable but received a '{target.GetType()?.Name}' instead");
}
return(null);
}
