tventura1337/fp1

Exploration 1

Programmer: Tony Ventura

My Library: JSON

For FP1, I explored the JSON library. I was able to convert a JSON expression into a string, read a JSON expression from a file, print them both, and test for valid JSON expressions.

To start my program off I first defined a string str. The string was a simple example I discovered on stackexchange:

(define str "{\"foo\": \"bar\", \"bar\": \"baz\"}")

Afterwards, I used string->jsexpr which does exactly as it's written. Writing (string->jsexpr str) would convert a string into a JSON expression. I defined this to be x in my program.

(define x (string->jsexpr str))

With a JSON expression x, it was easy to use jsexpr->string to convert my x back into a string. I defined this as y:

(define y (jsexpr->string x))

I then was able to read in a sample JSON file from the internet. This file will be named "test.json" in this repo. read-json reads a JSON expression from a valid input port, which ended up being (open-input-file "test.json") I defined this input to be z:

(define z (read-json (open-input-file "test.json")))

Finally I played around with (jsexpr? x) to determine json expressions. As per the documentation for (jsexpr? x), the procedure will return true when x is:

• the value of jsnull, 'null by default
• boolean?
• string?
• (or exact-integer? inexact-real?)
• (listof jsexpr?)
• (hasheqof symbol? jsexpr?)

My x, y, and z would be valid jsexpr, as would 'null as I haven't changed jsnull's default value. I worked out (jsexpr? 2.7+3i) as a test case that should fail which worked in my tests.

(jsexpr? 'null)  ;; #t
(jsexpr? 2.7+3i) ;; #f
(jsexpr? x)      ;; #t
(jsexpr? y)      ;; #t
(jsexpr? z)      ;; #t

Below is the output of my program, with spaced between each test.