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A Canonical S-expression (or csexp) is a binary encoding form of a subset of general S-expression. It was designed for use in SPKI to retain the power of S-expressions and ensure canonical form for applications such as digital signatures while achieving the compactness of a binary form and maximizing the speed of parsing. The particular subset of general S-expressions applicable here is composed of atoms, which are byte strings, and parentheses used to delimit lists or sub-lists. These S-expressions are fully recursive. While S-expressions are typically encoded as text, with spaces delimiting atoms and quotation marks used to surround atoms that contain spaces, when using the canonical encoding each atom is encoded as a length-prefixed byte string. No whitespace separating adjacent elements in a list is permitted. The length of an atom is expressed as an ASCII decimal number followed by a ":". == Example == The sexp (this "Canonical S-expression" has 5 atoms) becomes the csexp (4:this22:Canonical S-expression3:has1:55:atoms) Note that no quotation marks are required to escape the space character internal to the atom "Canonical S-expression", because the length prefix clearly points to the end of the atom. Note also that there is no whitespace separating an atom from the next element in the list. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Canonical S-expressions」の詳細全文を読む スポンサード リンク
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