Port

Check if a value is a port

Given a file named “main.scm” with:

(import (scheme base))

(write-u8 (if (port? <expression>) 65 66))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Examples

expression
(current-input-port)
(current-output-port)

Check if a value is an input port

Given a file named “main.scm” with:

(import (scheme base))

(write-u8 (if (input-port? (current-input-port)) 65 66))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Check if a value is an output port

Given a file named “main.scm” with:

(import (scheme base))

(write-u8 (if (output-port? <expression>) 65 66))

When I successfully run stak main.scm

Then the stdout should contain exactly “A”.

Examples

expression
(current-output-port)
(current-error-port)