Data Type Declarations and Restrictions

Starting in Qore 0.8.0, it is possible to restrict variables, class members, and function and method parameters to certain data types. This allows programmers to write safer code, as many more errors can be caught at parse time that would otherwise be caught at run time. Furthermore, providing type information to the parser allows Qore to implement performance optimizations by performing lookups and resolutions once at parse time rather than every time a variable or class member is accessed at run time.

When types are declared in a parameter list, functions and methods can be overloaded as well.

The types in the following table can be used as well as any class name or '*classname' (i.e. an asterix followed by the class name), meaning either the given class or NOTHING (no value).

Data Type Declaration Names

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
int	Integer	Integer	Restricts values Integer values
float	Float or Integer	Float	Restricts values to Float values
number	Number, Float, or Integer	Number	Restricts values to Number values
bool	Boolean	Boolean	Restricts values to Boolean values
string	String	String	Restricts values to String values
date	Date	Date	Restricts values to Date values; values may be either absolute or relative
binary	Binary	Binary	Restricts values to Binary values
hash	Hash	Hash	Restricts values to Hash values without any key type information
hash<...>	Hash	Hash	Restricts values to values of the referenced type-safe hash
hash<string, ...>	Hash	Hash	Restricts key values to the declared type
list	List	List	Restricts values to List values
list<...>	List	List	Restricts list values to the declared type
object	Object	Object	Restricts values to Object values
object<...>	Object	Object	Restricts values to objects of the specific class
<classname>	Object	Object	Restricts values to objects of the specific class given; either the class name can be given (ex: Mutex or a qualified path to the class: Qore::Thread::Mutex)
null	NULL	NULL	Restricts values to Qore's NULL type; this type has few (if any) practical applications and has been included for completeness' sake
nothing	NOTHING	NOTHING	Restricts values to Qore's NOTHING type; this type is mostly useful for declaring that a function or method returns no value
timeout	Integer, Date	Integer	Accepts Integer, Date and converts dates to an integer value representing milliseconds and returns the integer; incoming integers are assumed to represent milliseconds
base64binary	String, NULL	Float	Accepts String, NULL and converts a base-64 encoded string to a binary value and returns the new value
hexbinary	String, NULL	Float	Accepts String, NULL and converts a string of hex digits to a binary value and returns the new value
softbinary	String, NULL	Float	Accepts String, NULL and converts non-binary values to a binary value and returns the new value
softint	Integer, Float, Number, Boolean, String, NULL	Integer	Accepts Integer, Float, Boolean, String, NULL and converts non-integer values to an integer and returns the integer
softfloat	Integer, Float, Number, Boolean, String, NULL	Float	Accepts Integer, Float, Boolean, String, NULL and converts non-float values to a float and returns the new value
softnumber	Integer, Float, Number, Boolean, String, NULL	Float	Accepts Integer, Float, Boolean, String, NULL and converts non-number values to a float and returns the new value
softbool	Integer, Float, Number, Boolean, String, NULL	Boolean	Accepts Integer, Float, Boolean, String, NULL and converts non-boolean values to a boolean and returns the new value
softstring	Integer, Float, Number, Boolean, String, NULL	String	Accepts Integer, Float, Boolean, String, NULL and converts non-string values to a string and returns the new value
softdate	Integer, Float, Number, Boolean, String, Date, NULL	Date	Accepts Integer, Float, Boolean, String, Date, and NULL and converts non-date values to a date and returns the new value
softlist	all types	List	Accepts all types; NOTHING is returned as an empty list; a list is returned unchanged, and any other type is returned as the first element of a new list
softlist<...>	all types	List	Accepts all data types; NOTHING is returned as an empty list; a list is returned with its elements processed by the subtype declaration, and any other type is returned as the first element of a new list, also processed by the subtype declaration
data	String or Binary	same as received	Restricts input to String and Binary and returns the same type
code	Closures, Call References	same as received	Restricts values to closures and call references
reference	References	the type the reference points to	Restricts values to references to lvalues
reference<...>	References	the type given as an argument	Restricts values to references to lvalues compatible with the given type
*int	Integer, NULL, or NOTHING	Integer or NOTHING	Restricts values to Qore's Integer or NOTHING types; if NULL is passed then NOTHING is returned
*float	Float, NULL, or NOTHING	Float or NOTHING	Restricts values to Qore's Float or NOTHING types; if NULL is passed then NOTHING is returned
*number	Number, NULL, or NOTHING	Number or Number	Restricts values to Qore's Number or NOTHING types; if NULL is passed then NOTHING is returned
*bool	Boolean, NULL, or NOTHING	Boolean or NOTHING	Restricts values to Qore's Boolean or NOTHING types; if NULL is passed then NOTHING is returned
*string	String, NULL, or NOTHING	String or NOTHING	Restricts values to Qore's String or NOTHING types; if NULL is passed then NOTHING is returned
*date	Date, NULL, or NOTHING	Date or NOTHING	Restricts values to Qore's Date or NOTHING type; values may be either absolute or relative date/time values; if NULL is passed then NOTHING is returned
*binary	Binary, NULL, or NOTHING	Binary or NOTHING	Restricts values to Qore's Binary or NOTHING types; if NULL is passed then NOTHING is returned
*hash	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts values to Qore's Hash or NOTHING types; if NULL is passed then NOTHING is returned
*hash<...>	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts values to values of the referenced type-safe hash or NOTHING types; if NULL is passed then NOTHING is returned
*hash<string, ...>	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts key values to the declared complex hash or NOTHING types; if NULL is passed then NOTHING is returned
*list	List, NULL, or NOTHING	List or NOTHING	Accepts either a List or NOTHING; if NULL is passed then NOTHING is returned
*list<...>	List, NULL, or NOTHING	List or NOTHING	Restricts list values to the declared complex list type or NOTHING; if NULL is passed then NOTHING is returned
*object	Object, NULL, or NOTHING	Object or NOTHING	Accepts either an Object or NOTHING; if NULL is passed then NOTHING is returned
*<classname>	Object of the given class, NULL, or NOTHING	Object of the given class or NOTHING	Restricts values to objects of the specific class given or NOTHING; either the class name can be given (ex: *Mutex or a qualified path to the class: *Qore::Thread::Mutex); if NULL is passed then NOTHING is returned
*object<...>	Object of the given class, NULL, or NOTHING	Object of the given class or NOTHING	Restricts values to objects of the specific class given or NOTHING; if NULL is passed then NOTHING is returned
*null	NULL or NOTHING	NULL or NOTHING	Restricts input to NULL or NOTHING and returns the same type
*data	String, Binary, NULL, or NOTHING	String, Binary, or NOTHING	Restricts input to String, Binary, or NOTHING and returns the same type; if NULL is passed then NOTHING is returned
*code	Closures, Call References, NULL, or NOTHING	Closures, Call References, or NOTHING	Restricts values to closures, call references and NOTHING; if NULL is passed then NOTHING is returned
*timeout	Integer, Date, NULL, or NOTHING	Integer or NOTHING	Accepts Integer, Date and converts dates to an integer value representing milliseconds and returns the integer; incoming integers are assumed to represent milliseconds. If no value or NULL is passed, then NOTHING is returned
*reference	References, NULL, or NOTHING	the type the reference points to and NOTHING	Restricts values to references to lvalues and NOTHING; if NULL is passed then NOTHING is returned
*reference<...>	References, NULL, or NOTHING	the type given as an argument and NOTHING	Restricts values to references to lvalues compatible with the given type and NOTHING; if NULL is passed then NOTHING is returned
*softint	Integer, Float, Number, Boolean, String, NULL or NOTHING	Integer or NOTHING	Accepts Integer, Float, Number, Boolean, String, NULL and converts non-integer values to an integer and returns the integer. If no value or NULL is passed, then NOTHING is returned
*softfloat	Integer, Float, Number, Boolean, String, NULL or NOTHING	Float or NOTHING	Accepts Integer, Float, Number, Boolean, String, NULL and converts non-float values to a float and returns the new value. If no value or NULL is passed, then NOTHING is returned
*softnumber	Integer, Float, Number, Boolean, String, NULL or NOTHING	Number or NOTHING	Accepts Integer, Float, Number, Boolean, String, NULL and converts non-number values to a number and returns the new value. If no value or NULL is passed, then NOTHING is returned
*softbool	Integer, Float, Number, Boolean, String, NULL or NOTHING	Boolean or NOTHING	Accepts Integer, Float, Number, Boolean, String, NULL and converts non-boolean values to a boolean and returns the new value. If no value or NULL is passed, then NOTHING is returned
*softstring	Integer, Float, Number, Boolean, String, NULL or NOTHING	String or NOTHING	Accepts Integer, Float, Number, Boolean, String, NULL and converts non-string values to a string and returns the new value. If no value or NULL is passed, then NOTHING is returned
*softdate	Integer, Float, Number, Boolean, String, Date, NULL or NOTHING	Date or NOTHING	Accepts Integer, Float, Number, Boolean, String, Date, and NULL and converts non-date values to a date and returns the new value. If no value or NULL is passed, then NOTHING is returned
*softlist	all types	List or NOTHING	Accepts all types; NOTHING and list values are returned as the same value; NULL is returned as NOTHING, any other type is returned as the first element of a new list
*softlist<...>	all types	List or NOTHING	Accepts all data types; NOTHING and NULL are returned as NOTHING; a list is returned with its elements processed by the declared subtype, and any other type is returned as the first element of a new list with its element processed by the declared subtype
any	any	same as received	Provides no restrictions on the type of value it receives and returns the same value, however complex type information is stripped on assignment for backwards compatibility; note that the any type restriction is the same as using no type restriction; to assign any type without stripping complex types, use the auto type restriction instead
auto	all data types	all data types	Provides no restrictions on the type of value it receives and returns the same value; does not strip complex types on assignment like any

---

int

int Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
int	Integer	Integer	Restricts values to Qore's Integer type

Example

int sub foo(int i) {
    return i;
}

---

float

float Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
float	Float or Integer	Float	Restricts values to Qore's Float type

Example

float sub foo(float f = M_PI) {
    return f;
}

---

number

number Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
number	Number, Float, or Integer	Number	Restricts values to Qore's Number type

Example

number sub foo(number n = 2.35e40) {
    return n;
}

Since

Qore 0.8.6 introduced the number type

---

bool

bool Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
bool	Boolean	Boolean	Restricts values to Qore's Boolean type

Example

bool sub foo(bool b) {
    return b;
}

---

string

string Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
string	String	String	Restricts values to Qore's String type

Example

string sub foo(string str = "bar") {
    return str;
}

---

date

date Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
date	Date	Date	Restricts values to Qore's Date type; date/time values can be either absolute or relative

Example

date sub foo(date d = now_us()) {
    return d;
}

---

binary

binary Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
binary	Binary	Binary	Restricts values to Qore's Binary type

Example

binary sub foo(binary b) {
    return b;
}

---

hash

hash Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
hash	Hash (all)	Hash (untyped)	Restricts values to Qore's Hash type; if a typed hash is received, type information is removed for the lvalue assignment

Example

hash sub foo(hash h = ("foo": "bar", "x": 2)) {
    return h;
}

Type-Safe Hash Type

hashdecl Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
hash	hash<hashdecl>	hash<hashdecl>>	Restricts values to hashes created from the given hashdecl

The hash type takes a single type-safe hash name (or namespace- prefixed path) in angle brackets after "hash" which results in a type declaration restricted to the declared type-safe hash as in the following example.

Examples

# hashdecl typed hash declaration
hashdecl MyHash {
    string foo = "empty";
    int x = 1;
}
 
# declaration and initialization to default key values
hash<MyHash> h1();
 
# declaration and initialization with explicit values
hash<MyHash> h2(("foo": "string", "x": 10));
 
# declaration and initialization with the new operator
hash<MyHash> h3 = new hash<MyHash>(("foo": "string", "x": 10));
 
# example of a function with a typed hash return type and parameter type
hash<MyHash> sub foo(hash<MyHash> h = new hash<MyHash>("foo": "bar", "x": 2)) {
    return h;
}
 
# example of a function with a typed hash return type and a cast to a typed hash return type
hash<MyHash> sub foo(int x) {
    return cast<hash<MyHash>>(get_hash(x));
}

This type is supported at parse-time and at runtime; to convert such values to an untyped hash, assign it to a hash lvalue, use cast<hash>(...) on the value, call the hash() function on the value, or assign it to an untyped lvalue. Each of these options can be used to convert a type-safe hash to an untyped hash.

Complex type information is lost when assigning to an lvalue with a compatible but more generic type or by assigning to an untyped lvalue; this was necessary to allow complex types to be introduced in Qore without breaking backwards compatibility.

However, a special single argument, "auto", allows for the lvalue to maintain the complex hash type as in the following example:

hash h0 = ("a": 2, "b": 3);
# prints "hash"
printf("%y\n", h0.fullType());
hash<auto> h1 = new hash<MyHash>();
# prints "hash<MyHash>"
printf("%y\n", h1.fullType());

See also

• Hashdecl: Type-Safe Hash Declarations
• new
• cast

Hash With Declared Value Type

Complex hash Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
hash	hash<string, type>	hash<string, type>	Restricts values to hashes with the given declared key type; use cast<>(...) to convert values to this type at runtime.

The hash type also supports two arguments in angle brackets to specify the key and value types, however the key type currently must always be string. This results in a hash where the keys and values must always be of the declared type. See the following example for more information.

Examples

# 1: declaration and initialization (identical to 2 and 3)
hash<string, int> h1((
    "code": 500,
    "type": 300,
    "value": 0,
));
 
# 2: declaration and initialization with the assignment operator (identical to 1 and 3)
hash<string, int> h2 = (
    "code": 500,
    "type": 300,
    "value": 0,
);
 
# 3: declaration and initialization with the new operator (identical to 1 and 2)
hash<string, int> h3 = new hash<string, int>((
    "code": 500,
    "type": 300,
    "value": 0,
));
 
# assignment from an untyped hash with the cast<> operator (can result in runtime type errors)
hash<string, int> h4 = cast<hash<string, int>>(get_hash());

This type is supported at parse-time and at runtime; to convert such values to an untyped hash, assign it to a hash lvalue, use cast<hash>(...) on the value, call the hash() function on the value, or assign it to an untyped lvalue. Each of these options can be used to convert a type-safe hash to an untyped hash.

Complex type information is lost when assigning to an lvalue with a compatible but more generic type or by assigning to an untyped lvalue; this was necessary to allow complex types to be introduced in Qore without breaking backwards compatibility.

However, a special single argument, "auto", allows for the lvalue to maintain the complex hash type as in the following example:

hash h0 = ("a": 2, "b": 3);
# prints "hash"
printf("%y\n", h0.fullType());
hash<auto> h1 = ("a": 2, "b": 3);
# prints "hash<string, int>"
printf("%y\n", h1.fullType());

See also

• Hashdecl: Type-Safe Hash Declarations
• new
• cast

---

list

list Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
list	List	List	Restricts values to Qore's List type

Example

list sub foo(list l = ("foo", "bar")) {
    return l;
}

List With Declared Value Type

Complex list Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
list	list<type>	list<type>	Restricts values to lists with the given declared value type; use cast<>(...) to convert values to this type at runtime.

The list type supports one type argument in angle brackets to specify the value type. This results in a list where the values must always be of the declared type. See the following example for more information.

Examples

# 1: declaration and initialization (identical to 2 and 3)
list<int> l1(500, 300, 0);
 
# 2: declaration and initialization with the assignment operator (identical to 1 and 3)
list<int> l2 = (500, 300, 0);
 
# 3: declaration and initialization with the new operator (identical to 1 and 2)
list<int> l3 = new list<int>(500, 300, 0);
 
# assignment from an untyped list with the cast<> operator (can result in runtime type errors)
list<int> l4 = cast<list<int>>(get_list());

This type is supported at parse-time and at runtime; to convert such values to an untyped list, assign it to a list lvalue, use cast<list>(...) on the value, call the list() function on the value, or assign it to an untyped lvalue. Each of these options can be used to convert a type-safe list to an untyped list.

Complex type information is lost when assigning to an lvalue with a compatible but more generic type or by assigning to an untyped lvalue; this was necessary to allow complex types to be introduced in Qore without breaking backwards compatibility.

However, a special single argument, "auto", allows for the lvalue to maintain the complex list type as in the following example:

list l0 = (2, 3);
# prints "list"
printf("%y\n", l0.fullType());
list<auto> l1 = (2, 3);
# prints "list<int>"
printf("%y\n", l1.fullType());

See also

• new
• cast

---

object

object Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
object	Object	Object	Restricts values to Qore's Object type; note that any class name can also be used as a type restriction directly

Example

object sub foo(object o = new Mutex()) {
    return o;
}

Class-Specific Type Declaration

Complex object Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
object	object<class>	object<class>	Restricts values to objects of the given class

The object type declaration takes a single class name (or namespace- prefixed path) in angle brackets after "object" which results in a type declaration restricted to the declared class as in the following example.

Example

object<MyClass> sub foo(MyClass o = new MyClass()) {
    return o;
}

Note

this type declaration is equivalent to using the class name by itself

---

<classname>

<classname> Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
any class name	Object of the particular class given	Object of the particular class given	Restricts values to objects of the particular class given; subclasses are also accepted

Example

Mutex sub foo(Qore::Thread::Mutex m = new Mutex()) {
    return m;
}

---

null

null Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
null	NULL	NULL	Restricts values to Qore's NULL type; this type has few (if any) practical applications and has been included for completeness' sake

Example

# I don't know if this type has any useful/practical applications...
null n = NULL;

---

nothing

nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
nothing	NOTHING	NOTHING	Restricts values to Qore's NOTHING type; this type is mostly useful for declaring that a function or method returns no value

Example

nothing sub bar() {
    printf("foo\n");
}

---

timeout

timeout Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
timeout	Integer, Date	Integer	Accepts Integer, Date values and converts dates to an integer value representing milliseconds and returns the integer; incoming integers are assumed to represent milliseconds

Example

timeout sub foo(timeout to = 1250ms) {
    return to;
}

Note

Assigned variables of this type return integers where a single unit equals one millisecond; when an integer is converted to a date/time value, it is converted with a single unit equalling one second, therefore unexpected values can result when performing arithmetic operations with these values. Qore handles simple addition and subtraction correctly with mixed date/time values and timeout variables when the variable is used directly in the operation, but other operations will most likely not produce the expected results. It's recommended to avoid doing direct arithmetic with timeout values for this reason.

---

base64binary

base64binary Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
base64binary	String, Binary	Binary	Accepts String values by converting base64-encoded strings to a binary value and returns the binary

Example

base64binary sub foo(base64binary n = "qw==") {
    return n;
}

Note

invalid base64-encoded strings cause an exception to be thrown

See also

• softbinary
• hexbinary

Since

Qore 1.7 introduced the base64binary type

---

hexbinary

hexbinary Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
hexbinary	String, Binary	Binary	Accepts String values by converting hex strings to a binary value and returns the binary

Example

binary sub foo(hexbinary n = "abcd") {
    return n;
}

Note

hex binary strings must have an even number of characters, any invalid characters cause an exception to be thrown

See also

• base64binary
• softbinary

Since

Qore 1.7 introduced the hexbinary type

---

softbinary

softbinary Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softbinary	String, Binary	Binary	Accepts String values and converts non-binary values to a binary directly and returns the binary

Example

softbinary sub foo(softbinary n = "1000") {
    return n;
}

See also

• base64binary
• hexbinary

Since

Qore 0.9.5 introduced the softbinary type

---

softint

softint Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softint	Integer, Float, Number, Boolean, String, NULL	Integer	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-integer values to an integer and returns the integer

Example

softint sub foo(softint i = "1000") {
    # note that "200" will be converted to an integer on return
    return i > 500 ? "200" : i;
}

---

softfloat

softfloat Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softfloat	Integer, Float, Number, Boolean, String, NULL	Float	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-float values to a float and returns the float

Example

softfloat sub foo(softfloat f = "1000") {
    # note that "200" will be converted to a float on return
    return f > 500.0 ? "200" : f;
}

---

softnumber

softnumber Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softnumber	Integer, Float, Number, Boolean, String, NULL	number	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-number values to a number and returns the number

Example

softnumber sub foo(softnumber n = "1000") {
    # note that "200" will be converted to a number on return
    return n > 500.0n ? "200" : n;
}

Since

Qore 0.8.6 introduced the softnumber type

---

softbool

softbool Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softbool	Integer, Float, Number, Boolean, String, NULL	Boolean	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-boolean values to a boolean and returns the boolean

Example

softbool b = "0.5";

---

softstring

softstring Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softstring	Integer, Float, Number, Boolean, String, NULL	String	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-string values to a string and returns the string

Example

softstring str = 200;

---

softdate

softdate Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softdate	Integer, Float, Number, Boolean, String, Date, NULL	Date	Accepts Integer, Float, Number, Boolean, String, Date, and NULL values and converts non-date values to a date and returns the date

Example

softdate d = "2001-10-10T20:00:05 +04:00";

---

softlist

softlist Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softlist	all data types	List	Accepts all data types; NOTHING is returned as an empty list; a list is returned unchanged, and any other type is returned as the first element of a new list

Example

softlist sub foo(softlist l) {
    foreach any element in (\l) {
    }
    return l;
}

Softlist With Declared Value Type

Complex list Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
softlist	all data types	List	Accepts all data types; NOTHING is returned as an empty list; a list is returned with its elements processed by the subtype declaration, and any other type is returned as the first element of a new list, also processed by the subtype declaration

The softlist type supports one type argument in angle brackets to specify the value type. This results in a list where the values must always be of the declared type. See the following example for more information.

Examples

# 1: declaration and initialization (identical to 2 and 3)
softlist<int> l1(500, 300, 0);
 
# 2: declaration and initialization with the assignment operator (identical to 1 and 3)
softlist<int> l2 = (500, 300, 0);
 
# 3: declaration and initialization with the new operator (identical to 1 and 2)
softlist<int> l3 = new list<int>(500, 300, 0);
 
# assignment from an untyped list with the cast<> operator (can result in runtime type errors)
softlist<int> l4 = cast<list<int>>(get_list());

This type is supported at parse-time and at runtime; to convert such values to an untyped list, assign it to a list lvalue, use cast<list>(...) on the value, call the list() function on the value, or assign it to an untyped lvalue. Each of these options can be used to convert a type-safe list to an untyped list.

Complex type information is lost when assigning to an lvalue with a compatible but more generic type or by assigning to an untyped lvalue; this was necessary to allow complex types to be introduced in Qore without breaking backwards compatibility.

However, a special single argument, "auto", allows for the lvalue to maintain the complex list type as in the following example:

softlist l0 = 1;
# prints "list"
printf("%y\n", l0.fullType());
softlist<auto> l1 = (1, );
# prints "list<int>"
printf("%y\n", l1.fullType());

See also

• new
• cast

Since

Qore 0.8.3 introduced the softlist type

---

data

data Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
data	String or Binary	same as received	Restricts values to String and Binary

Example

data sub foo(data d) {
    return d;
}

---

code

code Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
code	Closures, Call References	same as received	Restricts values to Closures and Call References

Example

sub foo(code c) {
    c();
}

Note

that also "closure" and "callref" are accepted as synonyms for "code" (they are not more specific than "code" but rather provide identical type restrictions)

---

reference

reference Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
reference	References	the type the reference points to	Requires a reference to an lvalue to be assigned

Example

sub foo(reference f) {
    f = 10;
}
 
int i;
foo(\i);

Reference With Declared LValue Type

Complex reference Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
reference	reference<type>	type as given as the arg	Restricts values to references to lvalues with a type compatible to that given as the type argument

The reference type supports one type argument in angle brackets to specify a compatible lvalue type. See the following example for more information.

Example

int i = 0;
reference<int> r = \i;

---

*int

*int Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*int	Integer, NULL, or NOTHING	Integer or NOTHING	Restricts values to Integer and NOTHING; if NULL is passed then NOTHING is returned

Example

*int sub foo(*int i) {
    return i;
}

---

*float

*float Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*float	Float, NULL, or NOTHING	Float or NOTHING	Restricts values to Float and NOTHING; if NULL is passed then NOTHING is returned

Example

*float sub foo(*float f) {
    return f;
}

---

*number

*number Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*number	Number, NULL, or NOTHING	Number or NOTHING	Restricts values to Number and NOTHING; if NULL is passed then NOTHING is returned

Example

*number sub foo(*number n) {
    return n;
}

Since

Qore 0.8.6 introduced the *number type

---

*bool

*bool Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*bool	Boolean, NULL, or NOTHING	Boolean or NOTHING	Restricts values to Boolean and NOTHING; if NULL is passed then NOTHING is returned

Example

*bool sub foo(*bool b) {
    return b;
}

---

*string

*string Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*string	String, NULL, or NOTHING	String or NOTHING	Restricts values to String and NOTHING; if NULL is passed then NOTHING is returned

Example

*string sub foo(*string str) {
    return str;
}

---

*date

*date Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*date	Date, NULL, or NOTHING	Date or NOTHING	Restricts values to Date and NOTHING; if NULL is passed then NOTHING is returned

Example

*date sub foo(*date str) {
    return str;
}

---

*binary

*binary Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*binary	Binary, NULL, or NOTHING	Binary or NOTHING	Restricts values to Binary and NOTHING; if NULL is passed then NOTHING is returned

Example

*binary sub foo(*binary b) {
    return b;
}

---

*hash

*hash Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*hash	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts values to Hash and NOTHING; if NULL is passed then NOTHING is returned

Example

*hash sub foo(*hash h) {
    return h;
}

*hash<...>

Complex Hashdecl or Nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*hash<...>	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts values to values of the referenced type-safe hash or NOTHING types; if NULL is passed then NOTHING is returned

Example

*hash<MyHash> sub foo(*hash<MyHash> h) {
    return h;
}

*hash<string, ...>

Complex Hash or Nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*hash<string, ...>	Hash, NULL, or NOTHING	Hash or NOTHING	Restricts key values to the declared complex hash or NOTHING types; if NULL is passed then NOTHING is returned

Example

*hash<string, int> sub foo(*hash<string, int> h) {
    return h;
}

---

*list

*list Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*list	List or NOTHING	List or NOTHING	Restricts values to List and NOTHING; if NULL is passed then NOTHING is returned

Example

*list sub foo(*list l) {
    return l;
}

*list<...>

Complex List or Nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*list<...>	List, NULL, or NOTHING	List or NOTHING	Restricts list values to the declared complex list type or NOTHING; if NULL is passed then NOTHING is returned

Example

*list<int> sub foo(*list<int> l) {
    return l;
}

---

*object

*list Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*list	Object, NULL, or NOTHING	Object or NOTHING	Restricts values to Object and NOTHING; if NULL is passed then NOTHING is returned

Example

*object sub foo(*object obj) {
    return obj;
}

---

*<classname>

*<classname> Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*any class name	Object of the particular class given, NULL, or NOTHING	Object of the particular class given or NOTHING	Restricts values to objects of the particular class given or NOTHING; subclasses are also accepted; if NULL is passed then NOTHING is returned

Example

sub foo(*Mutex m) {
}

---

*null

null Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
null	NULL or NOTHING	NULL or NOTHING	Restricts values to Qore's NULL and NOTHING types; this type has few (if any) practical applications and has been included for completeness' sake

Example

# I don't know if this type has any useful/practical applications...
*null n = NULL;

---

*date

*data Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*data	String, Binary, NULL, or NOTHING	String, Binary, or NOTHING	Restricts values to String, Binary, and NOTHING; if NULL is passed then NOTHING is returned

Example

sub foo(*data d) {
}

---

*code

*code Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*code	Closures, Call References, NULL, or NOTHING	Closures, Call References, or NOTHING	Restricts values to Closures, Call References, and NOTHING; if NULL is passed then NOTHING is returned

Example

sub foo(*code c) {
}

---

*timeout

*timeout Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*timeout	Integer, Date, NULL, or NOTHING	Integer or NOTHING	converts dates to an integer value representing milliseconds and returns the integer; incoming integers are assumed to represent milliseconds; also accepts NOTHING and returns NOTHING; if NULL is passed then NOTHING is returned

Example

sub foo(*timeout c) {
}

Note

Assigned variables of this type return integers where a single unit equals one millisecond; when an integer is converted to a date/time value, it is converted with a single unit equalling one second, therefore unexpected values can result when performing arithmetic operations with these values. Qore handles simple addition and subtraction correctly with mixed date/time values and timeout variables when the variable is used directly in the operation, but other operations will most likely not produce the expected results. It's recommended to avoid doing direct arithmetic with timeout values for this reason.

---

*reference

*reference Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
reference	References, NULL, or NOTHING	the type the reference points to	Requires a reference to an lvalue to be assigned or NOTHING; if NULL is passed then NOTHING is returned

Example

sub foo(*reference f) {
    f = 10;
}
 
int i;
foo(\i);

*reference<...>

complex Reference or Nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*reference<...>	References, NULL, or NOTHING	the type given as an argument and NOTHING	Restricts values to references to lvalues compatible with the given type and NOTHING; if NULL is passed then NOTHING is returned

Example

sub foo(*reference<int> f) {
    f = 10;
}
 
int i;
foo(\i);

---

*softint

*softint Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softint	Integer, Float, Number, Boolean, String, NULL, NOTHING	Integer or NOTHING	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-integer values to an integer and returns the integer; also accepts NOTHING and NULL and returns NOTHING

Example

sub foo(*softint i) {
}

---

*softfloat

*softfloat Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softfloat	Integer, Float, Number, Boolean, String, NULL, NOTHING	Float or NOTHING	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-float values to a float and returns the float; also accepts NOTHING and NULL and returns NOTHING

Example

sub foo(*softfloat f) {
}

---

*softnumber

*softnumber Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softnumber	Integer, Float, Number, Boolean, String, NULL, NOTHING	Number or NOTHING	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-number values to a number and returns the number; also accepts NOTHING and NULL and returns NOTHING

Example

sub foo(*softnumber n) {
}

Since

Qore 0.8.6 introduced the *softnumber type

---

*softbool

*softbool Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softbool	Integer, Float, Number, Boolean, String, NULL, NOTHING	Boolean or NOTHING	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-boolean values to a boolean and returns the boolean; also accepts NOTHING and NULL and returns NOTHING

Example

sub foo(*softbool b) {
}

---

*softstring

*softstring Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softstring	Integer, Float, Number, Boolean, String, NULL, NOTHING	String or NOTHING	Accepts Integer, Float, Number, Boolean, String, and NULL values and converts non-string values to a string and returns the string; also accepts NOTHING and returns NOTHING

Example

sub foo(*softstring str) {
}

---

*softdate

*softdate Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softdate	Integer, Float, Number, Boolean, String, Date, NULL, NOTHING	String or NOTHING	Accepts Integer, Float, Number, Boolean, String, Date, and NULL values and converts non-date values to a date and returns the date; also accepts NOTHING and NULL and returns NOTHING

Example

sub foo(*softdate d) {
}

---

*softlist

*softlist Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softlist	all data types	List or NOTHING	Accepts all data types; NOTHING and NULL are returned as NOTHING; a list is returned unchanged, and any other type is returned as the first element of a new list

Example

*softlist d = v;

*softlist<...>

Complex Softlist or Nothing Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
*softlist	all data types	List or NOTHING	Accepts all data types; NOTHING and NULL are returned as NOTHING; a list is returned with its elements processed by the declared subtype, and any other type is returned as the first element of a new list with its element processed by the declared subtype

Example

*softlist<softint> sub foo() {
    # returns a list with 2 as the first element
    return "2";
}

Since

Qore 0.8.3 introduced the *softlist type

---

any

any Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
any	all data types	all data types	Provides no restrictions on the type of value it receives and returns the same value, however complex type information is stripped on assignment for backwards compatibility

Example

any v = bar;
any l = (1, 2);
# prints "list" as the complex type info is stripped on assignment for backwards compatibility
printf("%s\n", l.fullType());

Note

• The any type restriction is the same as using no type restriction
• To assign any type without stripping complex types, use the auto type restriction instead
• In general auto is recommended over any

---

auto

auto Type Restriction

Name	Accepts Qore Type(s)	Returns Qore Type(s)	Description
auto	all data types	all data types	Provides no restrictions on the type of value it receives and returns the same value; does not strip complex types on assignment like any

Example

auto v = bar;
auto l = (1, 2);
# prints "list<int>"
printf("%s\n", l.fullType());

• In general auto is recommended over any