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)
Except where otherwise noted, this document is licensed under Creative Commons Attribution 3.0 License. See all OpenStack Legal Documents.