Converting Primitive Types

You can convert any variable of a primitive type to another primitive type, by using the following syntax.

expression.primitive-type

The following example shows the conversion of a Date primitive type to a String primitive type.

writeDate(date: Date);
begin
    write "The date is " & date.String;
end;

As the changing of collection membership of primitive types is not supported by the reorganization process, a warning message is displayed when a collection membership of primitive types is changed from one primitive type to another and the class is already marked for reorganization or the change will cause the class to be marked for reorganization.

Converting any primitive value to a Binary primitive type obtains the internal representation of that value. Conversion of this intermediate Binary value to any type other than the original type may produce a different value from a direct conversion. For this reason, converting a primitive value from one type to another using an intermediate Binary value is not recommended. See also "Binary Primitive Type Conversions".

The following example shows an Integer primitive type being converted to a Real primitive type through an intermediate Binary value.

vars
    i : Integer;
begin
    i := 10;
    write i.Real;         //outputs 10
    write i.Binary.Real;  //outputs 4.94065645841247e-323    Not recommended
end;

The following table lists the effect of converting to the Byte and Character primitive types. Conversions from the MemoryAddress, Point, Date, Time, TimeStamp, TimeStampInterval, and TimeStampOffset types are not permitted.

From	To Byte	To Character
Binary	The first byte is copied.	In a Unicode system, the first two bytes of the Binary are taken as a Character (null‑padded, if necessary). In an ANSI system, the first byte of the Binary is taken as a Character.

Boolean	If true, the character is converted to 1; false is converted to zero (0).	If true, the character with ANSI or Unicode value equal to 1; if false, the Character with ANSI or Unicode value equal to zero (0).

Byte	No change.	Character with ANSI or Unicode value equal to the value of the Byte.

Character	Numeric value in the range zero (0) through 255. If the value of the Character in a Unicode system is outside this range, an exception is raised.	No change.

Decimal	Numeric value, truncated if necessary. If the resulting Byte value is outside the range zero (0) through 255.9999, an exception is raised.	Character with ANSI or Unicode value equal to the integer part of the number. If the resulting Character value is outside the range -255 through 255 ANSI, an exception is raised. For Unicode, the range that can be converted is zero (0) through 65535.9999, with no exception being raised.

Integer and Integer64	Numeric value (an exception is raised if the value exceeds the maximum size of the target).	Character with ANSI or Unicode value equal to the number. If the resulting Character value is outside the range zero (0) through 255 ANSI or the range zero (0) through 65535 Unicode, an exception is raised.

Real	Numeric value, truncated if necessary. If the resulting Byte value is outside the range zero (0) through 255, an exception is raised.	Character with ANSI or Unicode value equal to the integer part of the number. If the resulting Character value is outside the range zero (0) through 255 ANSI or the range zero (0) through 65535 Unicode, an exception is raised.

String and StringUtf8	Numeric value represented by the string of digits. Only US‑ASCII characters in the range zero (0) through 9 are recognized. The string can contain an optional string of tab and space characters, an optional sign, or a string of numeric values. The first unrecognized character ends the conversion. If the string cannot be converted to a numeric value, JADE returns zero (0), as shown in the following examples. "abc".Byte = 0 "12abc".Byte = 12 Overflow exceptions occur if the result of the conversion is too large. Use the isByte method to check the contents of a string.	First character.

The following table lists the effect of converting to the Boolean primitive type. Conversion from the MemoryAddress and Point types is not permitted.

From	To Boolean
Binary	If all bits in the first byte are zero (0), then false; else true
Boolean	No change
Byte	If all bits are zero (0), then false; else true
Character	If null, then false; else true
Date	If null, then false; else true
Decimal	If zero (0), then false; else true
Integer and Integer64	If zero (0), then false; else true
Real	If zero (0), then false; else true
String and StringUtf8	If "true", then true; else false
Time	If null, then false; else true
TimeStamp	If null, then false; else true
TimeStampInterval	If null, then false; else true
TimeStampOffset	If null, then false; else true

The following table lists the effect of converting to the String and StringUtf8 primitive types.

From	To String and StringUtf8
Binary	A direct binary copy is made, which when converted to a StringUtf8, may result in an illegal byte sequence.
Boolean	true is converted to "true"; false is converted to "false".
Byte	Binary value of the Byte in a decimal format.
Character	One-character string.
Date	Date in the format dd MMMM yyyy. If the receiver has the invalid value, the string is *"invalid"*. If the receiver is zero (0), an empty string is returned. The resulting string is always limited to ASCII digits and characters, it is never locale‑sensitive, and English month names are used.
Decimal	Decimal number formatted to the required number of decimal places.
Integer and Integer64	Integer value.
MemoryAddress	Memory address in a hexadecimal number format.
Point	Cartesian coordinates in the format x,y.
Real	Number displayed in expanded form.
String and StringUtf8	Typecasting assumes that the string to be converted contains ASCII characters only. Use the asString and asStringUtf8 methods for conversions based on a locale in an ANSI system.
Time	Time in the format hh:mm:ss.
TimeStamp	Date and time in the format dd MMMM yyyy, hh:mm:ss.
TimeStampInterval	Timestamp interval in the format d:hh:mm:ss.fff.
TimeStampOffset	Timestamp offset in the format d:hh:mm:ss.fff +\|-hhmm.

The following table lists the effect of converting to the Integer and Integer64 primitive types. Conversions from the MemoryAddress, Point, TimeStamp, TimeStampInterval, and TimeStampOffset primitive types are not permitted.

From	To Integer and Integer64
Binary	First 4 or 8 bytes are copied as the Integer or Integer64 result, respectively. If the Binary value has fewer than 4 bytes or 8 bytes, the converted result is padded with null bytes.
Boolean	true is converted to 1; false is converted to zero (0).
Byte	Numeric value in the range zero (0) through 255.
Character	Numeric value in the range zero (0) through 255 for an ANSI system, or zero (0) through 65,535 for a Unicode system.
Date	Julian day number for Integer and Integer64.
Decimal	Numeric value, truncated if necessary.
Integer and Integer64	Numeric value (an exception occurs if the value exceeds the maximum size of the target type).
Real	Numeric value (an exception occurs if the value exceeds the maximum size of the target type).
String and StringUtf8	Numeric value represented by the string of digits. Only US-ASCII characters in the range zero (0) through 9 are recognized. The string can contain an optional string of tab and space characters, an optional sign, or a string of numeric values. The first unrecognized character ends the conversion. If the string cannot be converted to a numeric value, JADE returns zero (0), as shown in the following examples. "abc".Integer = 0 "12abc".Integer = 12 Overflow exceptions occur if the result of the conversion is too large. Use the isInteger method or the isInteger64 method to check the contents of a string.
Time	Milliseconds since midnight for Integer and Integer64.

The following table lists the effect of converting to the Decimal and Real primitive types. Conversions from MemoryAddress, Point, TimeStamp, TimeStampInterval, and TimeStampOffset types are not permitted.

From	To Decimal and Real
Binary	Sufficient bytes are copied to the Decimal or Real result (padded with null bytes, if necessary). The result of the conversion may not be meaningful.
Boolean	true = 1, false = 0.
Byte	Numeric value in the range zero (0) through 255.
Character	Numeric value in the range zero (0) through 255 for an ANSI system, or zero (0) through 65,535 for a Unicode system.
Date	Julian day number.
Decimal	Numeric value.
Integer and Integer64	Numeric value.
Real	Numeric value.
String and StringUtf8	Numeric value. Only US‑ASCII characters in the range 0 through 9 are recognized. The string can contain an optional string of tab and space characters, an optional sign, or a string of numeric values. The first unrecognized character ends the conversion. If the string cannot be converted to a numeric value, JADE returns zero (0), as shown in the following examples. "abc".Real = 0 "1.2abc".Decimal = 1.2 If you are uncertain of the contents of a string, call the isDecimal or the isReal method.
Time	Milliseconds since midnight.

The following table lists the effect of converting to the Date and Time primitive types. Conversions from Boolean, Byte, Character, MemoryAddress, Point, TimeStampInterval, and TimeStampOffset types are not permitted.

From	To Date	To Time
Binary	First 4 bytes are copied as the Date value. If the Binary value has fewer than 4 bytes, null bytes are used for padding. The result of conversion may not be meaningful.	First 4 bytes are copied as the Time value. If the Binary value has fewer than 4 bytes, null bytes are used for padding. The result of conversion may not be meaningful.
Date	No change.	Not permitted.
Decimal	Julian day number is converted to Date.	Milliseconds since midnight is converted to Time.
Integer and Integer64	Julian day number is converted to Date.	Milliseconds since midnight is converted to Time.
Real	Julian day number is converted to Date.	Milliseconds since midnight is converted to Time.
String and StringUtf8	Valid date string is converted to Date.	Valid time string hh:mm[:ss.fff] [pre‑or‑post‑noon‑indicator] is converted to Time. (For details, see the rules that apply when casting a string to a time, following this table.)
Time	Not permitted.	No change.
TimeStamp	Date part copied, Time part discarded.	Time part copied, Date part discarded.

When casting a string to a date, the following rules apply.

The String must contain the date elements in one of the following orders.
- <day><month><year>
- <month><day><year>
- <year><month><day>
The delimiter between date elements is a sequence of one or more non‑alphanumeric characters.
The day and year elements must be numeric. If the month element is not numeric, it must be a short (three‑character) or long English month name (case‑insensitive).
If the year element is one or two digits, it is assumed to be from the current century.
If the first element is numeric, it is assumed to be a year if it has:
- Four or more digits
- Two or more digits and the first separator begins with a colon (:)

When casting a string to a time, the following rules apply.

The delimiter between time elements is a single non‑alphanumeric characters.
The hour element must be numeric in the range 0 through 24 (inclusive).
The minute and second elements must be numeric in the range 0 through 59 (inclusive).
The millisecond element must be numeric in the range 0 through 999 (inclusive).
A term specifying pre- or post-noon (that is, case‑insensitive "am", "a.m.", "pm", or "p.m.") is valid only if the hour element is less than or equal to 12.
"12:00 a.m.".Time converts to 00:00:00.
"12:00 p.m.".Time converts to 12:00:00.

The following table lists the effect of converting to the TimeStamp and TimeStampInterval primitive types. Conversions from the Boolean, Byte, Character, Decimal, Integer, Integer64, MemoryAddress, Point, Real, and TimeStampOffset types are not permitted.

From	To TimeStamp	To TimeStampInterval
Binary	First 8 bytes are copied as the TimeStamp value. If the Binary value has fewer than 8 bytes, null bytes are used for padding. Result of conversion may not be meaningful.	First 8 bytes are copied as the TimeStampInterval value. If the Binary value has fewer than 8 bytes, null bytes are used for padding. Result of conversion may not be meaningful.
Date	Date copied, Time null.	Not permitted.
String and StringUtf8	Date and Time string converted to TimeStamp.	In the format ddd:hh:mm:ss.fff.
Time	Date null, Time copied.	Not permitted.
TimeStamp	No change.	Not permitted.
TimeStampInterval	Not permitted.	No change.