sidef-scripts/Decoding/base64_decoder.sf

#!/usr/bin/ruby

func base64_decode(str) {

    str.tr!('A-Za-z0-9+=', '', 'cd');
    str.sub!(/=+\z/, '');
    str.tr!('A-Za-z0-9+', %q[ -_]);

    str.split(60).map { |chunk|
        'u'.unpack('C'.pack(32 + (chunk.len * 3/4 -> int)) + chunk);
    }.join;
}

var base64_text = <<'BASE64';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BASE64

print base64_decode(base64_text);