converting number to string in lisp

lisp common-lisp itoa
elyashiv picture elyashiv · Apr 25, 2013 · Viewed 21.4k times · Source

I tried to find a lisp function to convert between numbers and strings and after a little googling I fond a function with the same name. when I entered (itoa 1) SLIME printed: 

Undefined function ITOA called with arguments (1) .

How can I do the conversion?

Answer

edem picture edem · Apr 25, 2013

From number to string:

(write-to-string 5)
"5"

you may transform a string to any numerical notation:

(write-to-string 341 :base 10)
"341"

From string to number:

(parse-integer "5")
5

with some trash

(parse-integer " 5 something not a number" :junk-allowed t)
5

Or use this:

(read-from-string "23 absd")
23

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