/* Title: Pure/General/symbol.scala
Author: Makarius
Detecting and recoding Isabelle symbols.
*/
package isabelle
import scala.io.Source
import scala.collection.mutable
import scala.util.matching.Regex
object Symbol
{
/* spaces */
val spc = ' '
val space = " "
private val static_spaces = space * 4000
def spaces(k: Int): String =
{
require(k >= 0)
if (k < static_spaces.length) static_spaces.substring(0, k)
else space * k
}
/* Symbol regexps */
private val plain = new Regex("""(?xs)
[^\\ \ud800-\udfff] | [\ud800-\udbff][\udc00-\udfff] """)
private val symbol = new Regex("""(?xs)
\\ < (?:
\^? [A-Za-z][A-Za-z0-9_']* |
\^raw: [\x20-\x7e\u0100-\uffff && [^.>]]* ) >""")
// FIXME cover bad surrogates!?
// FIXME check wrt. ML version
private val bad_symbol = new Regex("(?xs) (?!" + symbol + ")" +
""" \\ < (?: (?! \s | [\"`\\] | \(\* | \*\) | \{\* | \*\} ) . )*""")
// total pattern
val regex = new Regex(plain + "|" + symbol + "|" + bad_symbol + "| .")
/* basic matching */
def is_plain(c: Char): Boolean = !(c == '\\' || '\ud800' <= c && c <= '\udfff')
def is_wellformed(s: CharSequence): Boolean =
s.length == 1 && is_plain(s.charAt(0)) || !bad_symbol.pattern.matcher(s).matches
class Matcher(text: CharSequence)
{
private val matcher = regex.pattern.matcher(text)
def apply(start: Int, end: Int): Int =
{
require(0 <= start && start < end && end <= text.length)
if (is_plain(text.charAt(start))) 1
else {
matcher.region(start, end).lookingAt
matcher.group.length
}
}
}
/* iterator */
def iterator(text: CharSequence) = new Iterator[CharSequence]
{
private val matcher = new Matcher(text)
private var i = 0
def hasNext = i < text.length
def next = {
val n = matcher(i, text.length)
val s = text.subSequence(i, i + n)
i += n
s
}
}
/* decoding offsets */
class Index(text: CharSequence)
{
case class Entry(chr: Int, sym: Int)
val index: Array[Entry] =
{
val matcher = new Matcher(text)
val buf = new mutable.ArrayBuffer[Entry]
var chr = 0
var sym = 0
while (chr < text.length) {
val n = matcher(chr, text.length)
chr += n
sym += 1
if (n > 1) buf += Entry(chr, sym)
}
buf.toArray
}
def decode(sym: Int): Int =
{
val end = index.length
def bisect(a: Int, b: Int): Int =
{
if (a < b) {
val c = (a + b) / 2
if (sym < index(c).sym) bisect(a, c)
else if (c + 1 == end || sym < index(c + 1).sym) c
else bisect(c + 1, b)
}
else -1
}
val i = bisect(0, end)
if (i < 0) sym
else index(i).chr + sym - index(i).sym
}
}
/* recoding text */
private class Recoder(list: List[(String, String)])
{
private val (min, max) =
{
var min = '\uffff'
var max = '\u0000'
for ((x, _) <- list) {
val c = x(0)
if (c < min) min = c
if (c > max) max = c
}
(min, max)
}
private val table = Map[String, String]() ++ list
def recode(text: String): String =
{
val len = text.length
val matcher = regex.pattern.matcher(text)
val result = new StringBuilder(len)
var i = 0
while (i < len) {
val c = text(i)
if (min <= c && c <= max) {
matcher.region(i, len).lookingAt
val x = matcher.group
result.append(table.get(x) getOrElse x)
i = matcher.end
}
else { result.append(c); i += 1 }
}
result.toString
}
}
/** Symbol interpretation **/
class Interpretation(symbol_decls: List[String])
{
/* read symbols */
private val empty = new Regex("""(?xs) ^\s* (?: \#.* )? $ """)
private val key = new Regex("""(?xs) (.+): """)
private def read_decl(decl: String): (String, Map[String, String]) =
{
def err() = error("Bad symbol declaration: " + decl)
def read_props(props: List[String]): Map[String, String] =
{
props match {
case Nil => Map()
case _ :: Nil => err()
case key(x) :: y :: rest => read_props(rest) + (x -> y)
case _ => err()
}
}
decl.split("\\s+").toList match {
case sym :: props if sym.length > 1 && is_wellformed(sym) => (sym, read_props(props))
case _ => err()
}
}
private val symbols: List[(String, Map[String, String])] =
for (decl <- symbol_decls if !empty.pattern.matcher(decl).matches)
yield read_decl(decl)
/* misc properties */
val names: Map[String, String] =
{
val name = new Regex("""\\<([A-Za-z][A-Za-z0-9_']*)>""")
Map((for ((sym @ name(a), _) <- symbols) yield (sym -> a)): _*)
}
val abbrevs: Map[String, String] = Map((
for ((sym, props) <- symbols if props.isDefinedAt("abbrev"))
yield (sym -> props("abbrev"))): _*)
/* main recoder methods */
private val (decoder, encoder) =
{
val mapping =
for {
(sym, props) <- symbols
val code =
try { Integer.decode(props("code")).intValue }
catch {
case _: NoSuchElementException => error("Missing code for symbol " + sym)
case _: NumberFormatException => error("Bad code for symbol " + sym)
}
val ch = new String(Character.toChars(code))
} yield {
if (code < 128) error("Illegal ASCII code for symbol " + sym)
else (sym, ch)
}
(new Recoder(mapping),
new Recoder(mapping map { case (x, y) => (y, x) }))
}
def decode(text: String): String = decoder.recode(text)
def encode(text: String): String = encoder.recode(text)
/* classification */
private object Decode_Set
{
def apply(elems: String*): Set[String] =
{
val content = elems.toList
Set((content ::: content.map(decode)): _*)
}
}
private val letters = Decode_Set(
"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
"\\<A>", "\\<B>", "\\<C>", "\\<D>", "\\<E>", "\\<F>", "\\<G>",
"\\<H>", "\\<I>", "\\<J>", "\\<K>", "\\<L>", "\\<M>", "\\<N>",
"\\<O>", "\\<P>", "\\<Q>", "\\<R>", "\\<S>", "\\<T>", "\\<U>",
"\\<V>", "\\<W>", "\\<X>", "\\<Y>", "\\<Z>", "\\<a>", "\\<b>",
"\\<c>", "\\<d>", "\\<e>", "\\<f>", "\\<g>", "\\<h>", "\\<i>",
"\\<j>", "\\<k>", "\\<l>", "\\<m>", "\\<n>", "\\<o>", "\\<p>",
"\\<q>", "\\<r>", "\\<s>", "\\<t>", "\\<u>", "\\<v>", "\\<w>",
"\\<x>", "\\<y>", "\\<z>",
"\\<AA>", "\\<BB>", "\\<CC>", "\\<DD>", "\\<EE>", "\\<FF>",
"\\<GG>", "\\<HH>", "\\<II>", "\\<JJ>", "\\<KK>", "\\<LL>",
"\\<MM>", "\\<NN>", "\\<OO>", "\\<PP>", "\\<QQ>", "\\<RR>",
"\\<SS>", "\\<TT>", "\\<UU>", "\\<VV>", "\\<WW>", "\\<XX>",
"\\<YY>", "\\<ZZ>", "\\<aa>", "\\<bb>", "\\<cc>", "\\<dd>",
"\\<ee>", "\\<ff>", "\\<gg>", "\\<hh>", "\\<ii>", "\\<jj>",
"\\<kk>", "\\<ll>", "\\<mm>", "\\<nn>", "\\<oo>", "\\<pp>",
"\\<qq>", "\\<rr>", "\\<ss>", "\\<tt>", "\\<uu>", "\\<vv>",
"\\<ww>", "\\<xx>", "\\<yy>", "\\<zz>",
"\\<alpha>", "\\<beta>", "\\<gamma>", "\\<delta>", "\\<epsilon>",
"\\<zeta>", "\\<eta>", "\\<theta>", "\\<iota>", "\\<kappa>",
"\\<mu>", "\\<nu>", "\\<xi>", "\\<pi>", "\\<rho>", "\\<sigma>",
"\\<tau>", "\\<upsilon>", "\\<phi>", "\\<chi>", "\\<psi>",
"\\<omega>", "\\<Gamma>", "\\<Delta>", "\\<Theta>", "\\<Lambda>",
"\\<Xi>", "\\<Pi>", "\\<Sigma>", "\\<Upsilon>", "\\<Phi>",
"\\<Psi>", "\\<Omega>",
"\\<^isub>", "\\<^isup>")
private val blanks =
Decode_Set(space, "\t", "\n", "\u000B", "\f", "\r", "\\<spacespace>", "\\<^newline>")
private val sym_chars =
Set("!", "#", "$", "%", "&", "*", "+", "-", "/", "<", "=", ">", "?", "@", "^", "_", "|", "~")
def is_letter(sym: String): Boolean = letters.contains(sym)
def is_digit(sym: String): Boolean = sym.length == 1 && '0' <= sym(0) && sym(0) <= '9'
def is_quasi(sym: String): Boolean = sym == "_" || sym == "'"
def is_letdig(sym: String): Boolean = is_letter(sym) || is_digit(sym) || is_quasi(sym)
def is_blank(sym: String): Boolean = blanks.contains(sym)
def is_symbolic_char(sym: String): Boolean = sym_chars.contains(sym)
def is_symbolic(sym: String): Boolean = sym.startsWith("\\<") && !sym.startsWith("\\<^")
}
}