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Difference between revisions of "Declaring data"

(Values of type List)
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<br>
 
  
EGL native types are in three categories: <br>
 
 
:[[Declaring data#Values_of_simple_value_types|Simple value types]]:
 
 
::BigInt, Date, Decimal(''n''), Decimal(''n'', ''p''),
 
 
::Float, Int, SmallFloat, SmallInt, Timestamp(''pattern'')
 
 
:[[Declaring data#Values_of_simple_reference_types|Simple reference types]]:
 
 
::Decimal, Number, String (now a value type),
 
 
::Timestamp (now a value type)
 
 
:Other reference types:
 
 
::[[Declaring data#Any|Any]], [[Declaring data#Dictionary|Dictionary]], [[Declaring data#List|List]]
 
 
<br>Note:&nbsp;
 
 
*The '''as''' operator casts a value from one type to another.&nbsp;
 
*The '''isa''' operator tests whether a value is of a given type.&nbsp;
 
 
<br>See also [[Working with custom types|Working with custom types]].
 
 
<br>
 
 
= <br> '''Values of simple value types'''  =
 
 
<source lang="java">
 
/** Character value types. **/
 
/** Note: String without parameter will be a reference type in EDT 1.0. **/
 
 
// Defaults to "".
 
firstName String;
 
 
// Defaults to null.         
 
secondName String?;
 
 
// Initializes value to "John" and allows a future value to be null.       
 
thirdName String? = "John"; 
 
 
// Initializes the value, which is unchangeable.
 
// Note: the elements of constant lists and dictionaries are changeable.)
 
const LANGUAGE String = "EGL";       
 
 
 
/** Numeric value types. **/
 
 
// Defaults to 0.
 
someVal Int;               
 
 
// Defaults to 0.0.
 
coord Float;     
 
 
// Initializes value to 4.5
 
distance Float = 4.5;
 
 
// Initializes value to 4
 
newDistance int = distance as int;
 
 
// Defaults to 000.00.
 
// Can hold 5 digits total, with 2 after the decimal point.           
 
amount Decimal(5,2);       
 
 
 
/** Date-and-time value types. **/
 
 
// Defaults to today's date.
 
today Date;
 
 
// Initializes the date to 30 January 2015.
 
future Date = "01/30/2015";
 
 
// Defaults to now. the second declaration uses the default pattern.
 
now TIMESTAMP("ddHHmmssffffff");
 
later TIMESTAMP("yyyyMMddHHmmss");
 
 
 
/** Boolean type **/
 
 
// Defaults to false.       
 
toggle Boolean;           
 
</source>
 
 
= Values of simple reference types  =
 
 
<br>
 
 
<br>
 
 
= Values of type Any  =
 
 
<source lang="java">
 
 
 
</source>
 
 
= Values of type Dictionary  =
 
 
<source lang="java">
 
 
 
</source>
 
 
<br>
 
 
<br>
 
 
= Values of type List  =
 
 
<source lang="java">
 
 
// new dynamic array of size 0
 
vals Int[];             
 
 
// dynamic list, but not instantiated (vals must be instantiated before it can be accessed)
 
vals Int[]?;
 
 
// new dynamic array of size 4; all values set to their default value (0 in this example)             
 
vals Int[] = new Int[4]; 
 
 
// dynamic array, initialized with 4 values
 
names String[] = [ "Paul", "John", "George", "Ringo" ]; 
 
 
// assigns the first index in the array to "Bob"
 
names[1] = "Bob";                             
 
 
// assigns the last index in the array to "Ken"         
 
names[names.getSize()] = "Ken";               
 
 
// new dynamic array of size 0
 
cities String[];             
 
 
// appends a new value to the end of the array           
 
cities.appendElement("Delta");   
 
 
// appends two new values to the end of the list cities.
 
cities.appendAll([ "Denver", "Pueblo" ]); 
 
 
// removes the second value in the array
 
removeElement(2);                 
 
 
// removes all values from the array
 
cities.removeAll();                       
 
</source>
 
 
// In a constant list, the element values are changeable,
 
// but the name cannot refer to another list.
 
const MINIMUMNUMBERS INT[] = [1,2,3,4,5];
 
<br>
 
 
<br> <br>
 
 
<br>
 

Latest revision as of 11:54, 10 February 2012

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