Trinsic

Trinisic is a collection of useful functions that aid in extrinsic/intrinsic system construction.

client-form

(defgeneric client-form (client))

CLIENT-FORM returns a form that will return the current client when evaluated in the future. It is used during during macro-expansion so that the expanded code refers to correct client at execution time.

features-list

(defgeneric features-list (client)

Return a list of feature keywords to be merged with *FEATURES* for intrinsic clients. This generic function has NCONC method combination.

cell-value

(defgeneric cell-value (client name type))

Returns the current value of a cell in the client. For example (cell-value client 'cl:\*standard-output\* 'cl:variable) could be used to retrieve the value of *STANDARD-OUTPUT*.

setf cell-value

(defgeneric (setf cell-value) (new-value client name type))

Set the value of the cell.

valid-cell-value-p

(defgeneric valid-cell-value-p (client name type value))

Checks for valid values of a cell.

initial-cell-value

(defgeneric initial-cell-value (client name type))

Returns the proper initial value for a cell.

call-with-cell-value

(defgeneric call-with-cell-value (client name type value thunk))

Invokes THUNK with a cell value. For example:

(defmethod call-with-cell-value
    (client (name (eql 'cl:*standard-output*)) (type (eql 'cl:variable))
     value thunk)
  (let ((cl:*standard-output* value))
    (funcall thunk)))

make-define-interface

(defmacro make-define-interface
    ((&key client-form client-class intrinsic)
     declarations &body body))

MAKE-DEFINE-INTERFACE creates a macro in the current package called DEFINE-INTERFACE that used to create an interface in an intrinsic or extrinsic system. The macro DEFINE-INTERFACE will define an appropriate CLIENT-FORM method.

DECLARATIONS are a list of variable declarations each with the form (var symbol &key variable). A LET binding is established around BODY with these declarations. The value of VAR in this binding is as follows:

1. For intrinsic systems the initial value of VAR will be SYMBOL if SYMBOL is interned. If SYMBOL is uninterned the VAR will be set to an interned symbol in *PACKAGE* with same SYMBOL-NAME as SYMBOL.
2. For extrinsic systems the initial value of VAR will be an an interned symbol in *PACKAGE* with same SYMBOL-NAME as SYMBOL.
3. If the keyword argument :VARIABLE is supplied and is non-NIL then methods for CELL-VALUE, (SETF CELL-VALUE), and CALL-WITH-CELL-VALUE will be defined for a TYPE of CL:VARIABLE.

For intrinsic systems the DEFINE-INTERFACE macro created by MAKE-DEFINE-INTERFACE will also merge the features keywords from FEATURE-LIST into CL:*FEATURES* and disable package locks for the BODY via TRIVIAL-PACKAGE-LOCKS:WITH-UNLOCKED-SYSTEM-PACKAGES.