+"""
+
+This is a Pure Python module to hyphenate text.
+
+It is inspired by Ruby's Text::Hyphen, but currently reads standard *.dic files,
+that must be installed separately.
+
+In the future it's maybe nice if dictionaries could be distributed together with
+this module, in a slightly prepared form, like in Ruby's Text::Hyphen.
+
+Wilbert Berendsen, March 2008
+info@wilbertberendsen.nl
+
+License: LGPL.
+
+"""
+
+import sys
+import re
+
+__all__ = ("Hyphenator")
+
+# cache of per-file Hyph_dict objects
+hdcache = {}
+
+# precompile some stuff
+parse_hex = re.compile(r'\^{2}([0-9a-f]{2})').sub
+parse = re.compile(r'(\d?)(\D?)').findall
+
+def hexrepl(matchObj):
+ return unichr(int(matchObj.group(1), 16))
+
+
+class parse_alt(object):
+ """
+ Parse nonstandard hyphen pattern alternative.
+ The instance returns a special int with data about the current position
+ in the pattern when called with an odd value.
+ """
+ def __init__(self, pat, alt):
+ alt = alt.split(',')
+ self.change = alt[0]
+ if len(alt) > 2:
+ self.index = int(alt[1])
+ self.cut = int(alt[2]) + 1
+ else:
+ self.index = 1
+ self.cut = len(re.sub(r'[\d\.]', '', pat)) + 1
+ if pat.startswith('.'):
+ self.index += 1
+
+ def __call__(self, val):
+ self.index -= 1
+ val = int(val)
+ if val & 1:
+ return dint(val, (self.change, self.index, self.cut))
+ else:
+ return val
+
+
+class dint(int):
+ """
+ Just an int some other data can be stuck to in a data attribute.
+ Call with ref=other to use the data from the other dint.
+ """
+ def __new__(cls, value, data=None, ref=None):
+ obj = int.__new__(cls, value)
+ if ref and type(ref) == dint:
+ obj.data = ref.data
+ else:
+ obj.data = data
+ return obj
+
+
+class Hyph_dict(object):
+ """
+ Reads a hyph_*.dic file and stores the hyphenation patterns.
+ Parameters:
+ -filename : filename of hyph_*.dic to read
+ """
+ def __init__(self, filename):
+ self.patterns = {}
+ f = open(filename)
+ charset = f.readline().strip()
+ if charset.startswith('charset '):
+ charset = charset[8:].strip()
+
+ for pat in f:
+ pat = pat.decode(charset).strip()
+ if not pat or pat[0] == '%': continue
+ # replace ^^hh with the real character
+ pat = parse_hex(hexrepl, pat)
+ # read nonstandard hyphen alternatives
+ if '/' in pat:
+ pat, alt = pat.split('/', 1)
+ factory = parse_alt(pat, alt)
+ else:
+ factory = int
+ tag, value = zip(*[(s, factory(i or "0")) for i, s in parse(pat)])
+ # if only zeros, skip this pattern
+ if max(value) == 0: continue
+ # chop zeros from beginning and end, and store start offset.
+ start, end = 0, len(value)
+ while not value[start]: start += 1
+ while not value[end-1]: end -= 1
+ self.patterns[''.join(tag)] = start, value[start:end]
+ f.close()
+ self.cache = {}
+ self.maxlen = max(map(len, self.patterns.keys()))
+
+ def positions(self, word):
+ """
+ Returns a list of positions where the word can be hyphenated.
+ E.g. for the dutch word 'lettergrepen' this method returns
+ the list [3, 6, 9].
+
+ Each position is a 'data int' (dint) with a data attribute.
+ If the data attribute is not None, it contains a tuple with
+ information about nonstandard hyphenation at that point:
+ (change, index, cut)
+
+ change: is a string like 'ff=f', that describes how hyphenation
+ should take place.
+ index: where to substitute the change, counting from the current
+ point
+ cut: how many characters to remove while substituting the nonstandard
+ hyphenation
+ """
+ word = word.lower()
+ points = self.cache.get(word)
+ if points is None:
+ prepWord = '.%s.' % word
+ res = [0] * (len(prepWord) + 1)
+ for i in range(len(prepWord) - 1):
+ for j in range(i + 1, min(i + self.maxlen, len(prepWord)) + 1):
+ p = self.patterns.get(prepWord[i:j])
+ if p:
+ offset, value = p
+ s = slice(i + offset, i + offset + len(value))
+ res[s] = map(max, value, res[s])
+
+ points = [dint(i - 1, ref=r) for i, r in enumerate(res) if r % 2]
+ self.cache[word] = points
+ return points
+
+
+class Hyphenator(object):
+ """
+ Reads a hyph_*.dic file and stores the hyphenation patterns.
+ Provides methods to hyphenate strings in various ways.
+ Parameters:
+ -filename : filename of hyph_*.dic to read
+ -left: make the first syllabe not shorter than this
+ -right: make the last syllabe not shorter than this
+ -cache: if true (default), use a cached copy of the dic file, if possible
+
+ left and right may also later be changed:
+ h = Hyphenator(file)
+ h.left = 1
+ """
+ def __init__(self, filename, left=2, right=2, cache=True):
+ self.left = left
+ self.right = right
+ if not cache or filename not in hdcache:
+ hdcache[filename] = Hyph_dict(filename)
+ self.hd = hdcache[filename]
+
+ def positions(self, word):
+ """
+ Returns a list of positions where the word can be hyphenated.
+ See also Hyph_dict.positions. The points that are too far to
+ the left or right are removed.
+ """
+ right = len(word) - self.right
+ return [i for i in self.hd.positions(word) if self.left <= i <= right]
+
+ def iterate(self, word):
+ """
+ Iterate over all hyphenation possibilities, the longest first.
+ """
+ if isinstance(word, str):
+ word = word.decode('latin1')
+ for p in reversed(self.positions(word)):
+ if p.data:
+ # get the nonstandard hyphenation data
+ change, index, cut = p.data
+ if word.isupper():
+ change = change.upper()
+ c1, c2 = change.split('=')
+ yield word[:p+index] + c1, c2 + word[p+index+cut:]
+ else:
+ yield word[:p], word[p:]
+
+ def wrap(self, word, width, hyphen='-'):
+ """
+ Return the longest possible first part and the last part of the
+ hyphenated word. The first part has the hyphen already attached.
+ Returns None, if there is no hyphenation point before width, or
+ if the word could not be hyphenated.
+ """
+ width -= len(hyphen)
+ for w1, w2 in self.iterate(word):
+ if len(w1) <= width:
+ return w1 + hyphen, w2
+
+ def inserted(self, word, hyphen='-'):
+ """
+ Returns the word as a string with all the possible hyphens inserted.
+ E.g. for the dutch word 'lettergrepen' this method returns
+ the string 'let-ter-gre-pen'. The hyphen string to use can be
+ given as the second parameter, that defaults to '-'.
+ """
+ if isinstance(word, str):
+ word = word.decode('latin1')
+ l = list(word)
+ for p in reversed(self.positions(word)):
+ if p.data:
+ # get the nonstandard hyphenation data
+ change, index, cut = p.data
+ if word.isupper():
+ change = change.upper()
+ l[p + index : p + index + cut] = change.replace('=', hyphen)
+ else:
+ l.insert(p, hyphen)
+ return ''.join(l)
+
+ __call__ = iterate
+
+
+if __name__ == "__main__":
+
+ dict_file = sys.argv[1]
+ word = sys.argv[2].decode('latin1')
+
+ h = Hyphenator(dict_file, left=1, right=1)
+
+ for i in h(word):
+ print i
+
fnp / librarian.git / commitdiff