1 files changed, 113 insertions, 0 deletions
diff --git a/eutils/chan.go b/eutils/chan.go
new file mode 100644
index 0000000..3b6d2c1
--- /dev/null
+++ b/eutils/chan.go
@@ -0,0 +1,113 @@
+// ===========================================================================
+//
+//                            PUBLIC DOMAIN NOTICE
+//            National Center for Biotechnology Information (NCBI)
+//
+//  This software/database is a "United States Government Work" under the
+//  terms of the United States Copyright Act. It was written as part of
+//  the author's official duties as a United States Government employee and
+//  thus cannot be copyrighted. This software/database is freely available
+//  to the public for use. The National Library of Medicine and the U.S.
+//  Government do not place any restriction on its use or reproduction.
+//  We would, however, appreciate having the NCBI and the author cited in
+//  any work or product based on this material.
+//
+//  Although all reasonable efforts have been taken to ensure the accuracy
+//  and reliability of the software and data, the NLM and the U.S.
+//  Government do not and cannot warrant the performance or results that
+//  may be obtained by using this software or data. The NLM and the U.S.
+//  Government disclaim all warranties, express or implied, including
+//  warranties of performance, merchantability or fitness for any particular
+//  purpose.
+//
+// ===========================================================================
+//
+// File Name:  chan.go
+//
+// Author:  Jonathan Kans
+//
+// ==========================================================================
+
+package eutils
+
+import (
+	"io"
+	"os"
+	"strings"
+)
+
+// stringChanReader connect a string output channel to an io.Reader interface
+type stringChanReader struct {
+	c <-chan string
+	s string
+}
+
+func (r *stringChanReader) Read(b []byte) (n int, err error) {
+
+	if r.s != "" {
+		n = copy(b, []byte(r.s))
+		r.s = r.s[n:]
+		return
+	}
+
+	for str := range r.c {
+		r.s = str
+		n = copy(b, []byte(r.s))
+		r.s = r.s[n:]
+		return
+	}
+
+	return 0, io.EOF
+}
+
+// ChanToReader converts a string channel to an ioReader
+func ChanToReader(inp <-chan string) io.Reader {
+
+	if inp == nil {
+		return nil
+	}
+
+	return &stringChanReader{c: inp}
+}
+
+// ChanToStdout sends a string channel to stdout
+func ChanToStdout(inp <-chan string) {
+
+	if inp == nil {
+		return
+	}
+
+	last := ""
+
+	for str := range inp {
+		last = str
+		os.Stdout.WriteString(str)
+	}
+
+	if !strings.HasSuffix(last, "\n") {
+		os.Stdout.WriteString("\n")
+	}
+}
+
+// ChanToString converts a string channel to a string
+func ChanToString(inp <-chan string) string {
+
+	if inp == nil {
+		return ""
+	}
+
+	var buffer strings.Builder
+
+	last := ""
+
+	for str := range inp {
+		last = str
+		buffer.WriteString(str)
+	}
+
+	if !strings.HasSuffix(last, "\n") {
+		buffer.WriteString("\n")
+	}
+
+	return buffer.String()
+}