Notation used in Ruby API documentation
Module: db
Description: A layout query
Layout queries are the backbone of the "Search & replace" feature. Layout queries allow retrieval of data from layouts and manipulation of layouts. This object provides script binding for this feature. Layout queries are used by first creating a query object. Depending on the nature of the query, either execute or each can be used to execute the query. execute will run the query and return once the query is finished. execute is useful for running queries that don't return results such as "delete" or "with ... do" queries. each can be used when the results of the query need to be retrieved.
The each method will call a block a of code for every result available. It will provide a LayoutQueryIterator object that allows accessing the results of the query. Depending on the query, different attributes of the iterator object will be available. For example, "select" queries will fill the "data" attribute with an array of values corresponding to the columns of the selection.
Here is some sample code:
ly = RBA::CellView::active.layout
q = RBA::LayoutQuery::new("select cell.name, cell.bbox from *")
q.each(ly) do |iter|
puts "cell name: #{iter.data[0]}, bounding box: #{iter.data[1]}"
end
The LayoutQuery class has been introduced in version 0.25.
| new LayoutQuery ptr | new | (string query) | Creates a new query object from the given query string |
| [const] | LayoutQuery ptr | _const_cast | Returns a non-const reference to self. | |
| void | _create | Ensures the C++ object is created | ||
| void | _destroy | Explicitly destroys the object | ||
| [const] | bool | _destroyed? | Returns a value indicating whether the object was already destroyed | |
| [const] | bool | _is_const_object? | Returns a value indicating whether the reference is a const reference | |
| void | _manage | Marks the object as managed by the script side. | ||
| void | _unmanage | Marks the object as no longer owned by the script side. | ||
| [const,iter] | LayoutQueryIterator | each | (const Layout ptr layout, ExpressionContext ptr context = nil) | Executes the query and delivered the results iteratively. |
| void | execute | (Layout layout, ExpressionContext ptr context = nil) | Executes the query | |
| [const] | string[] | property_names | Gets a list of property names available. |
| void | create | Use of this method is deprecated. Use _create instead | ||
| void | destroy | Use of this method is deprecated. Use _destroy instead | ||
| [const] | bool | destroyed? | Use of this method is deprecated. Use _destroyed? instead | |
| [const] | bool | is_const_object? | Use of this method is deprecated. Use _is_const_object? instead |
_const_cast | Signature: [const] LayoutQuery ptr _const_cast Description: Returns a non-const reference to self. Basically, this method allows turning a const object reference to a non-const one. This method is provided as last resort to remove the constness from an object. Usually there is a good reason for a const object reference, so using this method may have undesired side effects. This method has been introduced in version 0.29.6. |
_create | Signature: void _create Description: Ensures the C++ object is created Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created. |
_destroy | Signature: void _destroy Description: Explicitly destroys the object Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing. |
_destroyed? | Signature: [const] bool _destroyed? Description: Returns a value indicating whether the object was already destroyed This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself. |
_is_const_object? | Signature: [const] bool _is_const_object? Description: Returns a value indicating whether the reference is a const reference This method returns true, if self is a const reference. In that case, only const methods may be called on self. |
_manage | Signature: void _manage Description: Marks the object as managed by the script side. After calling this method on an object, the script side will be responsible for the management of the object. This method may be called if an object is returned from a C++ function and the object is known not to be owned by any C++ instance. If necessary, the script side may delete the object if the script's reference is no longer required. Usually it's not required to call this method. It has been introduced in version 0.24. |
_unmanage | Signature: void _unmanage Description: Marks the object as no longer owned by the script side. Calling this method will make this object no longer owned by the script's memory management. Instead, the object must be managed in some other way. Usually this method may be called if it is known that some C++ object holds and manages this object. Technically speaking, this method will turn the script's reference into a weak reference. After the script engine decides to delete the reference, the object itself will still exist. If the object is not managed otherwise, memory leaks will occur. Usually it's not required to call this method. It has been introduced in version 0.24. |
create | Signature: void create Description: Ensures the C++ object is created Use of this method is deprecated. Use _create instead Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created. |
destroy | Signature: void destroy Description: Explicitly destroys the object Use of this method is deprecated. Use _destroy instead Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing. |
destroyed? | Signature: [const] bool destroyed? Description: Returns a value indicating whether the object was already destroyed Use of this method is deprecated. Use _destroyed? instead This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself. |
each | Signature: [const,iter] LayoutQueryIterator each (const Layout ptr layout, ExpressionContext ptr context = nil) Description: Executes the query and delivered the results iteratively. The argument to the block is a LayoutQueryIterator object which can be asked for specific results. The context argument allows supplying an expression execution context. This context can be used for example to supply variables for the execution. It has been added in version 0.26. |
execute | Signature: void execute (Layout layout, ExpressionContext ptr context = nil) Description: Executes the query This method can be used to execute "active" queries such as "delete" or "with ... do". It is basically equivalent to iterating over the query until it is done. The context argument allows supplying an expression execution context. This context can be used for example to supply variables for the execution. It has been added in version 0.26. |
is_const_object? | Signature: [const] bool is_const_object? Description: Returns a value indicating whether the reference is a const reference Use of this method is deprecated. Use _is_const_object? instead This method returns true, if self is a const reference. In that case, only const methods may be called on self. |
new | Signature: [static] new LayoutQuery ptr new (string query) Description: Creates a new query object from the given query string Python specific notes: |
property_names | Signature: [const] string[] property_names Description: Gets a list of property names available. The list of properties available from the query depends on the nature of the query. This method allows detection of the properties available. Within the query, all of these properties can be obtained from the query iterator using LayoutQueryIterator#get. |