Initial data commit

Task/FASTA-format/Wren/fasta-format.wren

@@ -0,0 +1,40 @@
+import "io" for File
+
+var checkNoSpaces = Fn.new { |s| !s.contains(" ") && !s.contains("\t") }
+
+var first = true
+
+var process = Fn.new { |line|
+    if (line[0] == ">") {
+        if (!first) System.print()
+        System.write("%(line[1..-1]): ")
+        if (first) first = false
+    } else if (first) {
+        Fiber.abort("File does not begin with '>'.")
+    } else if (checkNoSpaces.call(line)) {
+        System.write(line)
+    } else {
+        Fiber.abort("Sequence contains space(s).")
+    }
+}
+
+var fileName = "input.fasta"
+File.open(fileName) { |file|
+    var offset = 0
+    var line = ""
+    while(true) {
+        var b = file.readBytes(1, offset)
+        offset = offset + 1
+        if (b == "\n") {
+            process.call(line)
+            line = "" // reset line variable
+        } else if (b == "\r") { // Windows
+            // wait for following "\n"
+        } else if (b == "") { // end of stream
+            System.print()
+            return
+        } else {
+            line = line + b
+        }
+    }
+}