Problem Statement

In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.

Write a program that reads a FASTA file such as: Note that a high-quality implementation will not hold the entire file in memory at once; real FASTA files can be multiple gigabytes in size.

Let's start with the solution:

(defn fasta [pathname]
  (with-open [r (clojure.java.io/reader pathname)]
    (doseq [line (line-seq r)]
      (if (= (first line) \>)
          (print (format "%n%s: " (subs line 1)))
        (print line)))))