cond-expand

Expand an else clause

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  (else
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match an implemented feature

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  (r7rs
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match a missing feature

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  (foo
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “B”.

Match an implemented library

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library (scheme base))
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match a built-in library

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library <library>)
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Examples

library
(scheme char)
(scheme lazy)

library
(srfi 1)

Match an imported library

Given a file named “main.scm” with:

(import (scheme base) (scheme read))

(cond-expand
  ((library (scheme read))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match a library defined in a program

Given a file named “main.scm” with:

(define-library (foo)
  (export foo)

  (import (scheme base))

  (begin
    (define foo 65)))

(import (scheme base))

(cond-expand
  ((library (foo))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match a library in a load path

Given a file named “library/foo/bar.sld” with:

(define-library (foo bar)
  (export bar)

  (import (scheme base))

  (begin
    (define bar 65)))

And a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library (foo bar))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak -I library main.scm

Then the stdout should contain exactly “A”.

Match a missing library

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library (scheme miracle))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “B”.

Match a library missing in a load path

Given a directory named “library”

And a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library (foo bar))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak -I library main.scm

Then the stdout should contain exactly “B”.

Expand only a matched library clause

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((library (scheme miracle))
    (syntax-error "unexpected expansion"))
  (else
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Match an invalid feature

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((lib (scheme base))
    (write-u8 65))
  (else
    (write-u8 66)))

When I run stak main.scm

Then the exit status should not be 0.

Expand an empty clause

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand (r7rs))

When I successfully run stak main.scm

Then the exit status should be 0.

Expand an empty else clause

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand (else))

When I successfully run stak main.scm

Then the exit status should be 0.

Use a not requirement

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((not foo)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Use a not requirement with a library

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((not (library (scheme miracle)))
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Examine features

Given a file named “main.scm” with:

(import (scheme base))

(write-u8 (if (memq 'r7rs (features)) 65 66))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

and

Expand no requirement

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((and)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Expand a requirement

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((and r7rs)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Expand two requirements

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((and r7rs r7rs)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

or

Expand no requirement

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((or)
    (write-u8 65))
  (else
    (write-u8 66)))

When I successfully run stak main.scm

Then the stdout should contain exactly “B”.

Expand a requirement

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((or r7rs)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Expand two requirements

Given a file named “main.scm” with:

(import (scheme base))

(cond-expand
  ((or foo r7rs)
    (write-u8 65)))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.