List Manipulations - Create List
The Create List Deluge syntax enables the creation of new list.
A new list can be created in two ways:
- Using constructor.
- Using list functions that return list values as output / or by direct
assignment of one list to another.
Using constructor
A constructor is a special syntax provided to create a list. These
constructors also supports special qualifiers that enables the creation
of specific list like string-list or date-list that accepts only string
or date type values respectively. A constructor enables the creation
of both empty list and also list with some initial values. The constructors
for creating a list variable is given below:
{} - Holds list values of any type. Handy syntax for creating list
with some initial values.
List() - Holds list values of any type.
List:String() - Holds list values of type String.
List:Long() - Holds list values of type Long.
List:Date() - Holds list values of type Date.
List:Bool() - Holds list values of type Boolean - true/false.
List:Float() - Holds list values of type Float.
Using list functions that return list values as output / or by
direct assignment of one list to another
A new list can be created by using methods like sublist(), toList()
etc. that return a list as output. You can also create a new list
by directly assigning an already defined list to it. In these cases,
the new list created is usually not empty.
Syntax
<listname> = <listexpression/constructor>;
|
where,
<listname> - any user-defined name can be specified as list
name.
<listexpression/constructor> - the expression, value or list constructor
to initialize the list.
Example
In the following sample code, a List named list1 of type String
is defined in the on add -> on load block and initialized with
the List:String() constructor.
actions
{
on add
{
on load
{
list1 = List:String();
}
}
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In the following sample code,
- a string list named list2 is defined in the on add ->
on load block and initialized with string values.
- a general list named list3 is defined in the on add -> on load
block and initialized with string and number values.
actions
{
on add
{
on load
{
list2 = List:String({"hockey", "cricket", "football", "tennis"});
list3 = {1, 2, 3, 4, "party"};
}
}
}
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In the following sample code, a string list named list4 is defined
and initialized with the Deluge expression input.Country+input.Name
actions
{
on add
{
submit
{
type = button
displayname = "Submit"
on validate
{
list4 = List:String(input.Country + ", " + input.Name); }
}
}
}
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Using Script Builder
To create a list using the Script Builder, drag-n-drop the Create
List syntax as shown in the screen-shot below, click on the Edit
btton and specify the list variable and the List constructor.
Related Links
