// Generate a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup)
=> (string name) =>
{
var standardFunction = baseLookup(name);
if (standardFunction != null)
{
return(standardFunction);
}
if (name.StartsWith("lg."))
{
name = name.Substring(3);
}
var templateName = ParseTemplateName(name).pureTemplateName;
if (this.TemplateMap.ContainsKey(templateName))
{
return(new ExpressionEvaluator(templateName, ExpressionFunctions.Apply(this.TemplateEvaluator(name)), ReturnType.Object, this.ValidTemplateReference));
}
const string template = "template";
if (name.Equals(template))
{
return(new ExpressionEvaluator(template, ExpressionFunctions.Apply(this.TemplateFunction()), ReturnType.Object, this.ValidateTemplateFunction));
}
const string fromFile = "fromFile";
if (name.Equals(fromFile))
{
return(new ExpressionEvaluator(fromFile, ExpressionFunctions.Apply(this.FromFile()), ReturnType.String, ExpressionFunctions.ValidateUnaryString));
}
const string activityAttachment = "ActivityAttachment";
if (name.Equals(activityAttachment))
{
return(new ExpressionEvaluator(
activityAttachment,
ExpressionFunctions.Apply(this.ActivityAttachment()),
ReturnType.Object,
(expr) => ExpressionFunctions.ValidateOrder(expr, null, ReturnType.Object, ReturnType.String)));
}
const string isTemplate = "isTemplate";
if (name.Equals(isTemplate))
{
return(new ExpressionEvaluator(isTemplate, ExpressionFunctions.Apply(this.IsTemplate()), ReturnType.Boolean, ExpressionFunctions.ValidateUnaryString));
}
return(null);
};
// Generate a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup)
=> (string name) =>
{
var prebuiltPrefix = "prebuilt.";
if (name.StartsWith(prebuiltPrefix))
{
return(baseLookup(name.Substring(prebuiltPrefix.Length)));
}
var templateName = ParseTemplateName(name).pureTemplateName;
if (this.TemplateMap.ContainsKey(templateName))
{
return(new ExpressionEvaluator(templateName, BuiltInFunctions.Apply(this.TemplateEvaluator(name)), ReturnType.Object, this.ValidTemplateReference));
}
const string template = "template";
if (name.Equals(template))
{
return(new ExpressionEvaluator(template, BuiltInFunctions.Apply(this.TemplateFunction()), ReturnType.Object, this.ValidateTemplateFunction));
}
const string fromFile = "fromFile";
if (name.Equals(fromFile))
{
return(new ExpressionEvaluator(fromFile, BuiltInFunctions.Apply(this.FromFile()), ReturnType.String, BuiltInFunctions.ValidateUnaryString));
}
const string activityAttachment = "ActivityAttachment";
if (name.Equals(activityAttachment))
{
return(new ExpressionEvaluator(
activityAttachment,
BuiltInFunctions.Apply(this.ActivityAttachment()),
ReturnType.Object,
(expr) => BuiltInFunctions.ValidateOrder(expr, null, ReturnType.Object, ReturnType.String)));
}
const string isTemplate = "isTemplate";
if (name.Equals(isTemplate))
{
return(new ExpressionEvaluator(isTemplate, BuiltInFunctions.Apply(this.IsTemplate()), ReturnType.Boolean, BuiltInFunctions.ValidateUnaryString));
}
return(baseLookup(name));
};
// Genearte a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup)
=> (string name) =>
{
var prebuiltPrefix = "prebuilt.";
if (name.StartsWith(prebuiltPrefix))
{
return(baseLookup(name.Substring(prebuiltPrefix.Length)));
}
if (this.TemplateMap.ContainsKey(name))
{
return(new ExpressionEvaluator(name, BuiltInFunctions.Apply(this.TemplateEvaluator(name)), ReturnType.Object, this.ValidTemplateReference));
}
const string template = "template";
if (name.Equals(template))
{
return(new ExpressionEvaluator(template, BuiltInFunctions.Apply(this.TemplateFunction()), ReturnType.Object, this.ValidateTemplateFunction));
}
const string fromFile = "fromFile";
if (name.Equals(fromFile))
{
return(new ExpressionEvaluator(fromFile, BuiltInFunctions.Apply(this.FromFile()), ReturnType.String, this.ValidateFromFile));
}
const string activityAttachment = "ActivityAttachment";
if (name.Equals(activityAttachment))
{
return(new ExpressionEvaluator(activityAttachment, BuiltInFunctions.Apply(this.ActivityAttachment()), ReturnType.Object, this.ValidateActivityAttachment));
}
return(baseLookup(name));
};
// Genearte a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup, bool isExpander)
=> (string name) =>
{
var prebuiltPrefix = "prebuilt.";
if (name.StartsWith(prebuiltPrefix))
{
return(baseLookup(name.Substring(prebuiltPrefix.Length)));
}
if (this.TemplateMap.ContainsKey(name))
{
if (isExpander)
{
return(new ExpressionEvaluator(name, BuiltInFunctions.Apply(this.TemplateExpander(name)), ReturnType.String, this.ValidTemplateReference));
}
else
{
return(new ExpressionEvaluator(name, BuiltInFunctions.Apply(this.TemplateEvaluator(name)), ReturnType.String, this.ValidTemplateReference));
}
}
return(baseLookup(name));
};
// Genearte a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup)
=> (string name) =>
{
var prebuiltPrefix = "prebuilt.";
if (name.StartsWith(prebuiltPrefix))
{
return(baseLookup(name.Substring(prebuiltPrefix.Length)));
}
if (this.TemplateMap.ContainsKey(name))
{
return(new ExpressionEvaluator(name, BuiltInFunctions.Apply(this.TemplateEvaluator(name)), ReturnType.Object, this.ValidTemplateReference));
}
const string lgTemplate = "lgTemplate";
if (name.Equals(lgTemplate))
{
return(new ExpressionEvaluator(lgTemplate, BuiltInFunctions.Apply(this.LgTemplate()), ReturnType.Object, this.ValidateLgTemplate));
}
return(baseLookup(name));
};
#pragma warning restore CA2225 // Operator overloads have named alternates
/// <summary>
/// Parse an expression string into an expression object.
/// </summary>
/// <param name="expression">expression string.</param>
/// <param name="lookup">Optional function lookup when parsing the expression. Default is Expression.Lookup which uses Expression.Functions table.</param>
/// <returns>expression object.</returns>
public static Expression Parse(string expression, EvaluatorLookup lookup = null) => new ExpressionParser(lookup ?? Expression.Lookup).Parse(expression?.TrimStart('='));
public ExpressionTransformer(EvaluatorLookup lookup)
{
_lookupFunction = lookup;
}
/// <summary>
/// Initializes a new instance of the <see cref="ExpressionParser"/> class.
/// Constructor.
/// </summary>
/// <param name="lookup">Delegate to lookup evaluation information from type string.</param>
public ExpressionParser(EvaluatorLookup lookup = null)
{
EvaluatorLookup = lookup ?? Expression.Lookup;
}
/// <summary>
/// Initializes a new instance of the <see cref="ExpressionEngine"/> class.
/// Constructor.
/// </summary>
/// <param name="lookup">If present delegate to lookup evaluation information from type string.</param>
public ExpressionEngine(EvaluatorLookup lookup = null)
{
EvaluatorLookup = lookup ?? BuiltInFunctions.Lookup;
}
// Generate a new lookup function based on one lookup function
private EvaluatorLookup CustomizedEvaluatorLookup(EvaluatorLookup baseLookup, bool isExpander)
=> (string name) =>
{
var standardFunction = baseLookup(name);
if (standardFunction != null)
{
return(standardFunction);
}
var pointIndex = name.IndexOf('.');
if (pointIndex > 0)
{
var alias = name.Substring(0, pointIndex);
if (Templates.NamedReferences.ContainsKey(alias))
{
var realTemplateName = name.Substring(pointIndex + 1);
return(new ExpressionEvaluator(realTemplateName, FunctionUtils.Apply(this.EvaluateWithTemplates(realTemplateName, Templates.NamedReferences[alias])), ReturnType.Object));
}
}
if (name.StartsWith("lg.", StringComparison.Ordinal))
{
name = name.Substring(3);
}
if (this.TemplateMap.ContainsKey(name))
{
if (isExpander)
{
return(new ExpressionEvaluator(name, FunctionUtils.Apply(this.TemplateExpander(name)), ReturnType.Object, this.ValidTemplateReference));
}
else
{
return(new ExpressionEvaluator(name, FunctionUtils.Apply(this.TemplateEvaluator(name)), ReturnType.Object, this.ValidTemplateReference));
}
}
const string template = "template";
if (name.Equals(template, StringComparison.Ordinal))
{
return(new ExpressionEvaluator(template, FunctionUtils.Apply(this.TemplateFunction()), ReturnType.Object, this.ValidateTemplateFunction));
}
const string fromFile = "fromFile";
if (name.Equals(fromFile, StringComparison.Ordinal))
{
return(new ExpressionEvaluator(fromFile, FunctionUtils.Apply(this.FromFile()), ReturnType.String, ValidateFromFile));
}
const string activityAttachment = "ActivityAttachment";
if (name.Equals(activityAttachment, StringComparison.Ordinal))
{
return(new ExpressionEvaluator(
activityAttachment,
FunctionUtils.Apply(this.ActivityAttachment()),
ReturnType.Object,
(expr) => FunctionUtils.ValidateOrder(expr, null, ReturnType.Object, ReturnType.String)));
}
const string isTemplate = "isTemplate";
if (name.Equals(isTemplate, StringComparison.Ordinal))
{
return(new ExpressionEvaluator(isTemplate, FunctionUtils.Apply(this.IsTemplate()), ReturnType.Boolean, FunctionUtils.ValidateUnaryString));
}
const string expandText = "expandText";
if (name.Equals(expandText, StringComparison.Ordinal))
{
return(new ExpressionEvaluator(expandText, FunctionUtils.Apply(this.ExpandText()), ReturnType.Object, FunctionUtils.ValidateUnaryString));
}
return(null);
};
