Working with Libraries¶

Importing Standard Libraries¶

Every R7RS program starts by importing what it needs:

(import (scheme base))
(import (scheme write))
(display (+ 1 2))
(newline)

Multiple imports can be combined:

(import (scheme base)
        (scheme write)
        (scheme char))

Import Modifiers¶

;; Import only specific names — the names must be exports of that
;; library ((scheme base) has map but not filter, which is SRFI-1)
(import (only (scheme base) map for-each))

;; Import everything except certain names
(import (except (scheme base) error))

;; Rename on import
(import (rename (scheme base) (map scheme-map)))

;; Add a prefix to all imported names
(import (prefix (scheme char) char:))
(char:char-alphabetic? #\A)  ;=> #t

Available Libraries¶

Kaappi includes all 14 R7RS standard libraries, 178 SRFIs (12 built-in, 162 portable, three sub-library-only, plus the SRFI 261 naming convention), and four Kaappi extension libraries.

Standard R7RS Libraries (16)¶

Library	Exports	Description
`(scheme base)`	230+	Core procedures and syntax
`(scheme case-lambda)`	1	`case-lambda` syntax
`(scheme char)`	22	Unicode character operations
`(scheme complex)`	6	Complex number procedures
`(scheme cxr)`	28	Car/cdr compositions (3 and 4 deep)
`(scheme eval)`	3	`eval`, `environment`, `interaction-environment`
`(scheme file)`	10	File I/O
`(scheme inexact)`	12	Transcendental math (sin, cos, exp, log, ...)
`(scheme lazy)`	5	`delay`, `force`, promises
`(scheme load)`	1	`load`
`(scheme process-context)`	5	`exit`, `command-line`, environment variables
`(scheme r5rs)`	141	The R5RS identifier set, with `exact->inexact` / `inexact->exact` under their R5RS names
`(scheme read)`	1	`read`
`(scheme repl)`	1	`interaction-environment`
`(scheme time)`	3	`current-second`, jiffies
`(scheme write)`	7	`write`, `display`, `write-shared`

SRFI Libraries (178)¶

See the SRFI Support page for the complete list of all 178 supported SRFIs, built-in and portable.

Kaappi Extension Libraries¶

Library	Description
`(kaappi ffi)`	Foreign function interface (ffi-open, ffi-fn, ffi-callback, ffi-close)
`(kaappi fibers)`	Green threads (spawn, yield, fiber-join, channels)
`(kaappi parallel)`	Worker pools and parallel map over OS threads (make-pool, pool-submit, parallel-map)
`(kaappi diagnostics)`	Stable KP diagnostic codes on error objects (error-object-code)

Writing Your Own Library¶

Define libraries with define-library in .sld files. The Library Authoring guide covers the full syntax: export specifications, include, cond-expand, file naming, bytecode caching, and organization tips.

Library Search Paths¶

Kaappi searches for .sld files in this order:

The current directory (./)
The ./lib/ subdirectory
Directories specified with --lib-path

The library name (mylib math) maps to the file path mylib/math.sld.

kaappi --lib-path /path/to/libs program.scm

Next: Library Authoring