Reflection capabilities in MuranoPL.

Reflection capabilities in MuranoPL.

Reflection provides objects that describes MuranoPL classes and packages.

The first important function is typeinfo . Usage:

$typeInfo: typeinfo($someObject)

Now $typeInfo variable contains instance of type of $someObject (MuranoClass instance).

MuranoPL provide following abilities to reflection:

Types

Property Description
name name of MuranoPL class
version version (SemVer) of MuranoPL class.
ancestors list of class ancestors
properties list of class properties. See Properties
package package information. See Packages
methods list of methods. See Methods
type reference to type, which can be used as argument in engine functions

Example

- $typeInfo: typeinfo($)
...
# log name, version and package name of this class
- $log.info("This is "{class_name}/{version} from {package}",
     class_name => $typeInfo.name,
     version => str($typeInfo.version),
     package => $typeInfo.package.name))
- $log.info("Ancestors:")
- For: ancestor
  In: $typeInfo.ancestors
  Do:
    #log all ancestors names
    - $log.info("{ancestor_name}", ancestor_name => $ancestor.name)
# log full class version
- $log.info("{version}", version => str($typeInfo.version))
# create object with same class
- $newObject = new($typeInfo.type)

Properties

Property introspection

Property Description
name name of property
hasDefault boolean value. True, if property has default value, False otherwise
usage Usage property’s field. See Property usage for details
declaringType type - owner of declared property

Property access

Methods Description
$property.setValue($target, $value) set value of $property for object $target to $value
$property.getValue($target) get value of $property for object $target

Example

- $typeInfo: typeinfo($)
...
# select first property
- $selectedPropety: $typeInfo.properties.first()
# log property name
- $log.info("Hi, my name is {p_name}, p_name => $selectedProperty.name)
# set new property value
- $selectedProperty.setValue($, "new_value")
# log new property value using reflection
- $log.info("My new value is {value}", value => $selectedProperty.getValue($))
# also, if property static, $target can be null
- $log.info("Static property value is {value},
    value => $staticProperty.getValue(null))

Packages

Property Description
types list of types, declared in package
name package name
version package version

Example

- $typeInfo: typeinfo($)
...
- $packageRef: $typeInfo.package
- $log.info("This is package {p_name}/{p_version}",
    p_name => $packageRef.name,
    p_version => str($packageRef.version))
- $log.info("Types in package:")
- For: type_
  In: $packageRef.types
  Do:
    - $log.info("{typename}", typename => type_.name)

Methods

Methods properties

Property Description
name method’s name
declaringType type - owner of declared method
arguments list of method’s arguments. See Method arguments

Method invoking

Methods Description
$method.invoke($target, $arg1, ... $argN, kwarg1 => value1, ..., kwargN => valueN) call $target’s method $method with $arg1, …, $argN positional arguments and kwarg1, …. kwargN named arguments

Example

- $typeInfo: typeinfo($)
...
# select single method by name
- $selectedMethod: $typeInfo.methods.where($.name = sampleMethodName).single()
# log method name
- $log.info("Method name: {m_name}", m_name => $selectedMethod.name)
# log method arguments names
- For: argument
  In: $selectedMethod.arguments
  Do:
     - $log.info("{name}", name => $argument.name)
# call method with positional argument 'bar' and named `baz` == 'baz'
- $selectedMethod.invoke($, 'bar', baz => baz)

Method arguments

Property Description
name argument’s name
hasDefault True if argument has default value, False otherwise
declaringMethod method - owner of argument
usage argument’s usage type. See Method arguments for details
- $firstArgument: $selectedMethod.arguments.first()
# store argument's name
- $argName: $firstArgument.name
# store owner's name
- $methodName: $firstArgument.declaringMethod.name
- $log.info("Hi, my name is {a_name} ! My owner is {m_name}",
    a_name => $argName,
    m_name => $methodName)
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