35 lines
661 B
Go
35 lines
661 B
Go
package helpers
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import "strings"
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func Join(elems []interface{}, sep string) string {
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firstElemt, ok := elems[0].(string)
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if !ok {
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panic("cannot join a slice that contains something else than strings")
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}
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switch len(elems) {
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case 0:
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return ""
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case 1:
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return firstElemt
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}
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n := len(sep) * (len(elems) - 1)
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for i := 0; i < len(elems); i++ {
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n += len(elems[i].(string))
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}
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var b strings.Builder
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b.Grow(n)
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b.WriteString(firstElemt)
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for _, s := range elems[1:] {
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b.WriteString(sep)
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elem, ok := s.(string)
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if !ok {
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panic("cannot join a slice that contains something else than strings")
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}
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b.WriteString(elem)
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}
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return b.String()
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}
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