62 lines
929 B
Go
62 lines
929 B
Go
// A writer that wraps long text lines to a specified length.
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package textwrapper
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import (
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"io"
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)
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type writer struct {
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Sep string
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Len int
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w io.Writer
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i int
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}
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func (w *writer) Write(b []byte) (N int, err error) {
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to := w.Len - w.i
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for len(b) > to {
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var n int
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n, err = w.w.Write(b[:to])
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if err != nil {
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return
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}
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N += n
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b = b[to:]
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_, err = w.w.Write([]byte(w.Sep))
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if err != nil {
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return
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}
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w.i = 0
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to = w.Len
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}
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w.i += len(b)
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n, err := w.w.Write(b)
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if err != nil {
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return
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}
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N += n
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return
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}
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// Returns a writer that splits its input into multiple parts that have the same
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// length and adds a separator between these parts.
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func New(w io.Writer, sep string, l int) io.Writer {
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return &writer{
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Sep: sep,
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Len: l,
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w: w,
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}
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}
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// Creates a RFC822 text wrapper. It adds a CRLF (ie. \r\n) each 76 characters.
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func NewRFC822(w io.Writer) io.Writer {
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return New(w, "\r\n", 76)
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}
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