October 10th Wednesday (十月 十日 水曜日）

(syntax datum)                #'datum

  (quasisyntax <template>)      #`<template>
  unsyntax                      #,<template>
  unsyntax-splicing             #,@<template>

  The quasisyntax form is similar to syntax, but it allows parts of the quoted text to be evaluated, in a
manner similar to the operation of quasiquoted.

  Within a quasisyntax template, subforms of unsyntax and unsyntax-splicing forms are evaluated, and every-
thing else is treated as ordinary template material, as with "syntax".  The value of each unsyntax subform is
inserted into the output in place of the unsyntax form, while the value of each unsyntax-splicing subform is
spliced into the surrounding list or vector structure.  Uses of unsyntax and unsyntax-splicing are vaild only
within quasisyntax expressions.

  A quasisyntax expression may be nested, with each quasisyntax introducing a new level of syntax quotation
and each unsyntax or unsyntax-splicing taking away a level of quotation.  An expression nested within n quasi-
syntax expressions must be within n unsyntax or unsyntax-splicing expressions to be evaluated.

  Use of unsyntax and unsyntax-splicing with zero or more than one subform are vaild only in splicing (list or
vector) contexts.  (unsyntax template ...) is equivalent to (unsyntax template) ..., and (unsyntax-splicing
template ...) is equivalent to (unsyntax-splicing template) ... .  These forms are primarily useful as intermediate forms in the output of the quasisyntax expander.