Character

Check if a value is a character

Given a file named “main.scm” with:

(import (scheme base))

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

When I successfully run scheme main.scm

Then the stdout should contain exactly “A”.

Examples

expression
#\A
#\newline
(integer->char 65)

Check if a value is a whitespace

Given a file named “main.scm” with:

(import (scheme base) (scheme char))

(write-u8 (if (char-whitespace? <value>) 65 66))

When I successfully run scheme main.scm

Then the stdout should contain exactly “<output>”.

Examples

value	output
#\A	B
#\newline	A
#\return	A
#\space	A
#\tab	A

Write a character

Given a file named “main.scm” with:

(import (scheme base))

(write-char #\A)

When I successfully run scheme main.scm

Then the stdout should contain exactly “A”.

Write a newline character

Given a file named “main.scm” with:

(import (scheme base))

(write-char #\A)
(newline)
(write-char #\B)

When I successfully run scheme main.scm

Then the stdout should contain exactly:

A
B

Compare characters

Given a file named “main.scm” with:

(import (scheme base))

(write-u8 (if (<predicate> <characters>) 65 66))

When I successfully run scheme main.scm

Then the stdout should contain exactly “<output>”.

Examples

predicate	characters	output
char=?	#\A #\A	A
char=?	#\A #\B	B
char=?	#\A #\A #\A	A
char=?	#\A #\A #\B	B
char<?	#\A #\B	A
char<?	#\A #\A	B
char<?	#\A #\B #\C	A
char<?	#\A #\B #\B	B