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Arc: Type handling

Arc has functions to convert types and to determine the type of an object.

Type handling

Foundation annotate type obj
Tags the object with the given type.

>(type (annotate 'mac car)) mac

rep obj
Returns the underlying object for an annotated object

>(rep whilet) #<procedure>

sym x
Coerces x to a 'sym.

>(sym "a") a

Foundation coerce obj type [args]
Coerces object to a new type. A char can be coerced to int, string, or sym. A number can be coerced to int, char, or string (of specified base). A string can be coerced to sym, cons (char list), or int (of specified base). A list of characters can be coerced to a string. A symbol can be coerced to a string.

>(coerce "a" 'sym) a

>(coerce 65 'char) #\A

>(coerce 65 'int 2) 65

>(coerce "abc" 'cons) (#\a #\b #\c)

Foundation type object
Returns the type of an object (as a symbol). Possibilities are cons, sym, fn, char, string, int, num, table, output, input, socket, exception, or mac.

>(type 1) int

>(type car) fn

annotate type obj Tags the object with the given type.	>(type (annotate 'mac car)) mac
rep obj Returns the underlying object for an annotated object	>(rep whilet) #<procedure>
sym x Coerces x to a 'sym.	>(sym "a") a
coerce obj type [args] Coerces object to a new type. A char can be coerced to int, string, or sym. A number can be coerced to int, char, or string (of specified base). A string can be coerced to sym, cons (char list), or int (of specified base). A list of characters can be coerced to a string. A symbol can be coerced to a string.	>(coerce "a" 'sym) a >(coerce 65 'char) #\A >(coerce 65 'int 2) 65 >(coerce "abc" 'cons) (#\a #\b #\c)
type object Returns the type of an object (as a symbol). Possibilities are cons, sym, fn, char, string, int, num, table, output, input, socket, exception, or mac.	>(type 1) int >(type car) fn