backend.py
changeset 0 76005e62091d
child 14 d937e9d7c4fe
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/backend.py	Mon Jul 11 23:15:28 2016 +0200
@@ -0,0 +1,815 @@
+# 2.5.0 backend
+
+# written by VB.
+
+import re, codecs
+import fileinput
+import sys, traceback, exceptions, os
+from xml.sax.saxutils import escape, quoteattr
+from copy import deepcopy
+from glob import glob
+from pyPEG import code, parse, parseLine, u, Symbol
+from yml2 import ymlCStyle, comment, _inner
+
+ymlFunc, pointers, pythonFunc = {}, {}, {}
+in_ns = u""
+operator = []
+included = u""
+includePath = []
+emitlinenumbers = False
+encoding = "utf-8"
+
+first = True
+enable_tracing = False
+
+ymlFunc["decl"] = "#error"
+ymlFunc["define"] = "#error"
+ymlFunc["operator"] = "#error"
+
+def clearAll():
+    global ymlFunc, pointers, pythonFunc, in_ns, operator, included
+    ymlFunc, pointers, pythonFunc = {}, {}, {}
+    in_ns = u""
+    operator = []
+    included = u""
+
+lq = re.compile(r"\|(\>*)(.*)")
+sq = re.compile(r"(\d*)\>(.*)")
+ts = re.compile(r'(\|\|(?P<inds>\>*)\s*\n(?P<text1>.*?)\n(?P<base>\s*)\|\|)|("""(?P<text2>.*?)""")|(\>\>(?P<text3>.*?)\>\>)', re.S)
+tq = re.compile(r"(\]|\<)\s*(.*)")
+bq = re.compile(r"\`(.*?)\`", re.S)
+bqq = re.compile(r"\s*\`\`(.*)")
+all = re.compile(r".*", re.S)
+
+line = 1
+
+def pointer(name):
+    try:
+        return u(pointers[name[1:]])
+    except:
+        if name == "*_trace_info":
+            return u'""'
+        if included:
+            raise LookupError(u"in " + included + u":" + u(line) + u": pointer " + name)
+        else:
+            raise LookupError(u"in " + u(line) + u": pointer " + name)
+
+def evalPython(expr):
+    try:
+        result = eval(u(expr), pythonFunc)
+        if type(result) is str:
+            return codecs.decode(result, encoding)
+        else:
+            return result
+    except:
+        name, parm, tb = sys.exc_info()
+        msg = u"in python expression: " + u(parm)
+        if name is exceptions.SyntaxError:
+            tbl = traceback.format_exception(name, parm, tb)
+            msg += u"\n" + tbl[-3] + tbl[-2]
+        else:
+            msg += u": " + expr + u"\n"
+        if included:
+            raise name(u"in " + included + u":" + u(line) + u": " + msg)
+        else:
+            raise name(u"in " + u(line) + u": " + msg)
+    
+def execPython(script):
+    try:
+        if type(script) is unicode:
+            exec script in pythonFunc
+        else:
+            exec codecs.decode(script, encoding) in pythonFunc
+    except:
+        name, parm, tb = sys.exc_info()
+        msg = u"in python script: " + u(parm)
+        if name is exceptions.SyntaxError:
+            tbl = traceback.format_exception(name, parm, tb)
+            msg += u"\n" + tbl[-3] + tbl[-2]
+        else:
+            msg += u": " + expr + u"\n"
+        if included:
+            raise name(u"in " + included + u":" + u(line) + u": " + msg)
+        else:
+            raise name(u"in " + u(line) + u": " + msg)
+
+def textOut(text):
+    if not text:
+        return u""
+    if type(text) is not unicode:
+        text = codecs.decode(text, encoding)
+    text = text.replace(r'\"', r'\\"')
+    text = u'u"""' + text.replace('"', r'\"') + u'"""'
+    try:
+        textFunc = ymlFunc["text"]
+        parms = ['text', ('parm', [text])]
+        c, result = textFunc(parms)
+        if c:
+            if type(textFunc.alias) is unicode:
+                result += u"</" + textFunc.alias + u">"
+            else:
+                result += u"</" + codecs.decode(textFunc.alias, encoding) + u">"
+        return result
+    except:
+        return escape(eval(text))
+
+def strRepl(text):
+    if not text:
+        return u""
+    if type(text) is not unicode:
+        text = codecs.decode(text, encoding)
+    text = text.replace(r'\"', r'\\"')
+    text = u'u"""' + text.replace('"', r'\"') + u'"""'
+    if type(text) is unicode:
+        return escape(eval(text))
+
+def applyMacros(macros, text):
+    result = text
+    for key, value in macros.iteritems():
+        result = result.replace(key, value)
+    return result
+
+class YF:
+    def __init__(self, name):
+        self.name = name
+        self.parms = []
+        self.descends = []
+        self.values = {}
+        self.content = None
+        self.pointers = {}
+        self.macros = {}
+        if in_ns:
+            self.alias = in_ns + u":" + name.replace("_", "-")
+        else:
+            self.alias = name.replace("_", "-")
+        pythonFunc["yml_" + name] = self
+        if emitlinenumbers:
+            self.values["yml:declared"] = u(line)
+
+    def copy(self, newName):
+        yf = YF(newName)
+        yf.parms.extend(self.parms)
+        yf.descends.extend(self.descends)
+        yf.values = self.values.copy()
+        yf.content = self.content
+        yf.pointers = self.pointers.copy()
+        yf.macros = self.macros.copy()
+        yf.alias = self.alias
+        return yf
+
+    def patch(self, second):
+        self.parms.extend(second.parms)
+        self.descends.extend(second.descends)
+        self.values.update(second.values)
+        if second.content:
+            self.content = second.content
+        self.pointers.update(second.pointers)
+        self.macros.update(second.macros)
+
+    def __call__(self, called_with, hasContent = False, avoidTag = False):
+        global pointers
+        parms = []
+        vals = {}
+        if self.pointers:
+            pointers.update(self.pointers)
+   
+        for data in called_with:
+            if type(data) is tuple or type(data) is Symbol:
+                if data[0] == "parm":
+                    l = data[1]
+                    parm = l[0]
+                    if parm[0] == "*":
+                        parm = pointer(parm)
+                    if len(l) == 1:
+                        if type(parm) is tuple or type(parm) is Symbol:
+                            if parm[0] == "pyExp":
+                                val = evalPython(parm[1][0])
+                                parms.append(val)
+                        else:
+                            parms.append(evalPython((parm)))
+                    else:
+                        if type(parm) is tuple or type(parm) is Symbol:
+                            if parm[0] == "pyExp":
+                                parm = evalPython(parm[1][0])
+                        val = l[1]
+                        if type(val) is tuple or type(val) is Symbol:
+                            if val[0] == "pyExp":
+                                val = evalPython(val[1][0])
+                        if val[0] == "*":
+                            val = pointer(val)
+                        if u(val)[0] == '"' or u(val)[0] == "'":
+                            vals[parm] = evalPython(u(val))
+                        else:
+                            vals[parm] = u(val)
+                elif data[0] == "content":
+                    hasContent = True
+
+        if enable_tracing:
+            text = u(parms) + u", " + u(vals)
+            pointers["_trace_info"] = u'"' + u(line) + u": " + u(self.name) + u" " + text.replace(u'"', u'#') + u'"'
+
+        if emitlinenumbers:
+            global first
+            if first:
+                vals["xmlns:yml"] = u"http://fdik.org/yml"
+                first = False
+            vals["yml:called"] = u(line)
+        return self.xml(parms, vals, hasContent, avoidTag)
+
+    def addParm(self, parm):
+        if parm[0] == "%":
+            for i in range(len(self.parms)):
+                if self.parms[i][0] != "%":
+                    self.parms.insert(i, parm)
+                    return
+        self.parms.append(parm)
+
+    def addDescend(self, desc):
+        if desc[0] == "+" or desc[0] == "@":
+            self.descends.append(desc[1:])
+        else:
+            self.descends.append(desc)
+
+    def addValue(self, parm, value):
+        if type(value) is str or type(value) is unicode:
+            self.values[parm] = u(evalPython(value))
+        else:
+            self.values[parm] = u(evalPython(u(value)))
+
+    def xml(self, callParms, callValues, hasContent, avoidTag = False):
+        global pointers
+        extraContent = u""
+        if self.content:
+            hasContent = True
+        resultParms = self.values.copy()
+        macros = self.macros.copy()
+        toDelete = resultParms.keys()
+        for key in toDelete:
+            if key[0] == "*":
+                del resultParms[key]
+        for key, value in callValues.iteritems():
+            if key[0] == "%":
+                macros[key] = value
+            else:
+                resultParms[key] = value
+        i = 0
+        for cp in callParms:
+            if i < len(self.parms):
+                if self.parms[i][0] == "*":
+                    cp = u(cp)
+                    if "'" in cp:
+                        pointers[self.parms[i][1:]] = u'"' + cp + u'"'
+                    else:
+                        pointers[self.parms[i][1:]] = u"'" + cp + u"'"
+                elif self.parms[i][0] == "%":
+                    macros[self.parms[i]] = u(cp)
+                else:
+                    resultParms[self.parms[i]] = cp
+            else:
+                extraContent += u(cp)
+                hasContent = True
+            i += 1
+        result = u""
+        for p, v in resultParms.iteritems():
+            if p[0] == "'" or p[0] == '"':
+                p = eval(p)
+            result += u" "+ p + u"=" + quoteattr(applyMacros(macros, u(v)))
+        if hasContent:
+            if avoidTag:
+                return True, strRepl(extraContent)
+            else:
+                return True, u"<" + self.alias + result + u">" + strRepl(extraContent)
+        else:
+            if avoidTag:
+                return False, u""
+            else:
+                return False, u"<" + self.alias + result + u"/>"
+
+def replaceContent(tree, subtree):
+    n = 0
+    while n < len(tree):
+        obj = tree[n]
+        if obj[0] == "func":
+            l = obj[1]
+            if l[0] == "content":
+                d = 1
+                if subtree:
+                    for el in subtree:
+                        tree.insert(n+d, el)
+                        d += 1
+                del tree[n]
+                n += d
+            else:
+                try:
+                    if l[-1][0] == "content":
+                        replaceContent(l[-1][1], subtree)
+                except: pass
+        elif obj[0] == "funclist":
+            replaceContent(obj[1], subtree)
+        n += 1
+    return tree
+
+def executeCmd(text):
+    if type(text) is not unicode:
+        text = codecs.decode(text, encoding)
+    for (regex, pattern) in operator:
+        match = re.search(regex, text)
+        while match:
+            cmd = pattern
+            opt = match.groups()
+            for i in range(len(opt)):
+                cmd = cmd.replace(u"%" + u(i+1), opt[i])
+            text = text[:match.start()] + u"`" + cmd + u"`"+ text[match.end():]
+            match = re.search(regex, text)
+
+    result = u""
+    m = re.search(bq, text)
+    while text and m:
+        cmd  = m.group(1)
+        head = textOut(text[:m.start()])
+        text = text[m.end():]
+        try:
+            r, rest = parseLine(cmd, _inner, [], True, comment)
+            if rest: raise SyntaxError(cmd)
+        except SyntaxError:
+            if included:
+                raise SyntaxError(u"in " + included + u":" + u(line) + u": syntax error in executing command: " + cmd.strip())
+            else:
+                raise SyntaxError(u"in " + u(line) + u": syntax error in executing command: " + cmd.strip())
+        inner = _finish(r)
+        result += head + inner
+        m = re.search(bq, text)
+    result += textOut(text)
+
+    return result
+
+def codegen(obj):
+    global in_ns, pointers, line, included
+    ctype = obj[0]
+
+    if type(obj) is code:
+        return obj
+
+    try:
+        if ctype.line: line = ctype.line
+    except: pass
+
+    if ctype == "empty":
+        return code(u"")
+
+    if ctype == "in_ns":
+        in_ns = obj[1][0]
+        subtree = obj[1]
+        for sel in subtree:
+            codegen(sel)
+        in_ns = u""
+        return code(u"")
+
+    elif ctype == "decl":
+        name = u""
+        for data in obj[1]:
+            if type(data) is unicode or type(data) is str:
+                name = data
+                try:
+                    yf = ymlFunc[name]
+                    yf.alias
+                except:
+                    ymlFunc[name] = YF(name)
+                    yf = ymlFunc[name]
+                    if in_ns:
+                        yf.alias = in_ns + u":" + name
+                        if not enable_tracing:
+                            if in_ns == "xsl" and (name == "debug" or name=="assert" or name[:7]=="_trace_"):
+                                yf.alias = "-"
+                                yf.addParm("skip1")
+                                yf.addParm("skip2")
+                                break
+            elif type(data) is tuple or type(data) is Symbol:
+                if data[0] == "base":
+                    base = data[1][0]
+                    try:
+                        yf = ymlFunc[name] = ymlFunc[base].copy(name)
+                    except KeyError:
+                        if included:
+                            raise KeyError(u"in " + included + u":" + u(line) + u": " + base + u" as base for " + name)
+                        else:
+                            raise KeyError(u"in " + u(line) + u": " + base + u" as base for " + name)
+                elif data[0] == "shape":
+                    shape = ymlFunc[data[1]]
+                    try:
+                        yf = ymlFunc[name]
+                        yf.patch(shape)
+                    except KeyError:
+                        if included:
+                            raise KeyError(u"in " + included + u":" + u(line) + u": " + base + u" as shape for " + name)
+                        else:
+                            raise KeyError(u"in " + u(line) + u": " + base + u" as shape for " + name)
+                elif data[0] == "descend":
+                    yf.addDescend(data[1])
+                elif data[0] == "declParm":
+                    l = data[1]
+                    parmName = l[0]
+                    if len(l)==1:
+                        yf.addParm(parmName)
+                    else:
+                        value = l[1]
+                        if parmName[0] != "%":
+                            yf.addValue(parmName, value)
+                        if parmName[0] == "*":
+                            yf.pointers[parmName[1:]] = value
+                            yf.addParm(parmName)
+                        elif parmName[0] == "%":
+                            if type(value) is unicode or type(value) is str:
+                                yf.macros[parmName] = u(evalPython(value))
+                            else:
+                                yf.macros[parmName] = u(evalPython(u(value)))
+                            yf.addParm(parmName)
+                elif data[0] == "alias":
+                    if in_ns:
+                        yf.alias = in_ns + u":" + data[1][0]
+                    else:
+                        yf.alias = data[1][0]
+                elif data[0] == "content":
+                    yf.content = data[1]
+
+        return code(u"")
+
+    elif ctype == "funclist":
+        result = u""
+        for f in obj[1]:
+            result += codegen(f)
+        return code(result)
+
+    elif ctype == "parentheses":
+        if len(obj[1]):
+            return codegen(('func', ['_parentheses', ('content', [obj[1][0]])]))
+        else:
+            return u""
+
+    elif ctype == "fparm":
+        if len(obj[1]):
+            return codegen(('func', ['_parm', ('content', [obj[1][0]])]))
+        else:
+            return u""
+
+    elif ctype == "generic":
+        return codegen(('func', ['_generic', ('content', [obj[1][0]])]))
+
+    elif ctype == "xbase":
+        return codegen(('func', ['_base', ('content', [obj[1][0]])]))
+
+    elif ctype == "func":
+        avoidTag = False
+        name = obj[1][0]
+
+        if name == "decl":
+            if ymlFunc[name] == "#error":
+                if included:
+                    raise SyntaxError(u"in " + included + u":" + u(line) + u": syntax error in decl statement")
+                else:
+                    raise SyntaxError(u"in " + u(line) + u": syntax error in decl statement")
+        if name == "define" or name == "operator":
+            if ymlFunc[name] == "#error":
+                if included:
+                    raise SyntaxError(u"in " + included + u":" + u(line) + u": syntax error in define statement")
+                else:
+                    raise SyntaxError(u"in " + u(line) + u": syntax error in define statement")
+
+        if name[0] == "&":
+            avoidTag = True
+            name = name[1:]
+        hasContent = False
+
+        if len(name) > 2:
+            if name[0:2] == "**":
+                return code(eval('u'+pointer(name[1:])))
+
+        if name[0] == "*":
+            name = eval(pointer(name))
+            if name[0] == "&":
+                avoidTag = True
+                name = name[1:]
+
+        try:
+            ymlFunc[name]
+        except:
+            try:
+                ymlFunc["_"]
+                return codegen(('func', ['_', ('content', [('funclist', [obj])])]))
+            except:
+                ymlFunc[name] = YF(name)
+        
+        if ymlFunc[name].alias == "-": avoidTag = True
+
+        to_add = []
+        if len(ymlFunc[name].descends):
+            if obj[1][-1][0] != 'content':
+                if included:
+                    raise KeyError(u"in " + included + u":" + u(line) + u": " + name + u" has descending attributes, but no descendants are following")
+                else:
+                    raise KeyError(u"in " + u(line) + u": " + name + u" has descending attributes, but no descendants are following")
+
+            def first_func(obj):
+                if type(obj) is tuple or type(obj) is Symbol:
+                    if obj[0] == 'func':
+                        return obj
+                    elif obj[0] == 'funclist':
+                        return first_func(obj[1])
+                    elif obj[0] == 'content':
+                        return first_func(obj[1])
+                    else:
+                        return None
+                elif type(obj) == list:
+                    for e in obj:
+                        f = first_func(e)
+                        if f: return f
+                    return None
+
+            def copy_without_first_func(o, found = False):
+                c = []
+                for obj in o:
+                    if found:
+                        c.append(obj)
+                    else:
+                        if obj[0] == 'func':
+                            if obj[1][-1][0] == 'content':
+                                c.extend( obj[1][-1][1] )
+                            found = True
+                        else:
+                            c.append( ( obj[0], copy_without_first_func(obj[1], False ) ) )
+                return c
+
+            def get_parms(obj):
+                result = []
+                for e in obj[1]:
+                    if type(e) is tuple or type(e) is Symbol:
+                        if e[0] == "parm":
+                            result.append( e )
+                return result
+
+            try:
+                add_params = get_parms(obj)
+                for e in obj[1][-1][1]:
+                    c = e[1]
+                    for dname in ymlFunc[name].descends:
+                        f, c = first_func(c), copy_without_first_func(c)
+                        if dname[0] == "*":
+                            pointers[dname[1:]] = "'" + f[1][0] + "'"
+                        else:
+                            add_params.append( ('parm', [dname, u"'" + f[1][0] + u"'"]) )
+                        try:
+                            add_params.extend( get_parms(f) )
+                        except: pass
+
+                    new_things = [ e[1][0] ]
+                    new_things.extend( add_params )
+                    new_things.append( ('content', c) )
+                    
+                    to_add.append( ('func', new_things ) )
+            except:
+                if included:
+                    raise KeyError(u"in " + included + u":" + u(line) + u": " + name + u" has descending attributes, and too less descendants are following")
+                else:
+                    raise KeyError(u"in " + u(line) + u": " + name + u" has descending attributes, and too less descendants are following")
+
+        if not to_add:
+            to_add = ( obj, )
+
+        complete = u""
+
+        for obj in to_add:
+            subtree = None
+            try:
+                if obj[1][-1][0] == "content":
+                    subtree = obj[1][-1][1]
+            except: pass
+     
+            if ymlFunc[name].content:
+                hasContent = True
+                treetemplate = deepcopy(ymlFunc[name].content)
+                subtree = replaceContent(treetemplate, subtree)
+
+            if subtree:
+                hasContent = True
+
+            hasContent, result = ymlFunc[name](obj[1], hasContent, avoidTag)
+
+            if subtree:
+                for sel in subtree:
+                    result += codegen(sel)
+
+            if hasContent and not(avoidTag):
+                result += u"</" + ymlFunc[name].alias + u">"
+
+            complete += result
+
+        return code(complete)
+
+    elif ctype == "textsection":
+        result = u''
+        ll = obj[1].splitlines()
+        space = len(ll[-1]) - 2
+        for l in ll[1:-1]:
+            m = re.match(bqq, l)
+            if m:
+                cmd = m.group(1)
+                try:
+                    r, x = parseLine(cmd, _inner, [], True, comment)
+                    if x: raise SyntaxError(cmd)
+                    result += _finish(r)
+                except SyntaxError:
+                    if included:
+                        raise SyntaxError(u"in " + included + u":" + u(line) + u": syntax error in executing command: " + cmd.strip())
+                    else:
+                        raise SyntaxError(u"in " + u(line) + u": syntax error in executing command: " + cmd.strip())
+            else:
+                result += codegen(Symbol(u'lineQuote', u'| ' + l[space:]))
+        return code(result)
+
+    elif ctype == "lineQuote" or ctype == "quote":
+        m, text, base, inds = None, u"", 0, 0
+
+        if ctype == "lineQuote":
+            text = obj[1]
+            m = lq.match(text)
+            if m:
+                inds = len(m.group(1))
+                text = m.group(2)[1:]
+            else: inds = 0
+        elif ctype == "quote":
+            inds = -1
+            text = obj[1][0]
+            m = sq.match(text)
+            if m:
+                if m.group(1):
+                    inds = int(m.group(1))
+                text = m.group(2)[1:]
+            else:
+                if type(text) is unicode or type(text) is str:
+                    text = u(evalPython(text))
+
+        ind = u""
+        if inds > -1:
+            try:
+                cmd = evalPython(u"indent(" + u(inds) + u")")
+                result, rest = parseLine(u(cmd), _inner, [], True, comment)
+                if rest:
+                    raise SyntaxError()
+                ind = _finish(result)
+            except: pass
+        
+        if ctype == "lineQuote": text += u"\n"
+
+        hasTextFunc = False
+        try:
+            ymlFunc["text"]
+            hasTextFunc = True
+        except: pass
+
+        text = executeCmd(text)
+        return code(ind + text) 
+
+    elif ctype == "tagQuote":
+        m = tq.match(obj[1])
+        if m.group(1) == "<":
+            return code(u"<" + m.group(2))
+        else:
+            return code(m.group(2))
+
+    elif ctype == "operator":
+        operator.append((re.compile(evalPython(obj[1][0])), obj[1][1]))
+        return code(u"")
+
+    elif ctype == "constant":
+        name = obj[1][0]
+        if name[0] == "*":
+            name = name[1:]
+        value = obj[1][1]
+        pointers[name] = value
+        return code(u"")
+
+    elif ctype == "include":
+        reverse = False
+        ktext, kxml = False, False
+        for arg in obj[1]:
+            if type(arg) is tuple or type(arg) is Symbol:
+                if arg[0] == "reverse":
+                    reverse = True
+                elif arg[0] == "ktext":
+                    ktext = True
+                elif arg[0] == "kxml":
+                    kxml = True
+            elif type(arg) is unicode or type(arg) is str:
+                filemask = arg
+
+        if filemask[0] == '/' or filemask[0] == '.':
+            files = glob(filemask)
+        else:
+            files = []
+            for directory in includePath:
+                path = os.path.join(directory, filemask)
+                files.extend(glob(path))
+
+        if reverse:
+            files = files[-1::-1]
+
+        if not(files):
+            if included:
+                raise IOError(u"in " + included + ":" + u(line) + u": include file(s) '" + filemask + u"' not found")
+            else:
+                raise IOError(u"in " + u(line) + u": include file(s) '" + filemask + u"' not found")
+
+        includeFile = fileinput.input(files, mode="rU", openhook=fileinput.hook_encoded(encoding))
+        _included = included
+        if ktext or kxml:
+            text = u""
+            for line in includeFile:
+                included = includeFile.filename()
+                if kxml:
+                    if (not line[:6] == '<?xml ') and (not line[:6] == '<?XML '):
+                        text += line
+                else:
+                    text += executeCmd(line)
+            included = _included
+            return code(text)
+        else:
+            result = parse(ymlCStyle(), includeFile, True, comment)
+            included = u(filemask)
+            x = _finish(result)
+            included = _included
+            return code(x)
+
+    elif ctype == "pyExp":
+        exp = obj[1][0]
+        cmd = evalPython(exp)
+        result, rest = parseLine(u(cmd), _inner, [], True, comment)
+        if rest:
+            raise SyntaxError(cmd)
+        return code(_finish(result))
+
+    elif ctype == "pythonCall":
+        parms = []
+        data = obj[1]
+        for p in data:
+            if type(p) is unicode or type(p) is str:
+                name = p
+            elif type(p) is tuple or type(p) is Symbol:
+                ptype = p[0]
+                if ptype == "parm":
+                    if p[1][0][0] == "*":
+                        parms.append(pointer(p[1][0]))
+                    else:
+                        parms.append(p[1][0])
+        if len(parms) == 0:
+            exp = name + u"()"
+        elif len(parms) == 1:
+            exp = name + u"(" + u(parms[0]) + u")"
+        else:
+            exp = name + u(tuple(parms))
+        cmd = evalPython(exp)
+        result, rest = parseLine(u(cmd), _inner, [], True, comment)
+        if rest:
+            raise SyntaxError()
+        return code(_finish(result))
+
+    else:
+        return code(u"")
+
+def _finish(tree):
+    result = u""
+    python = u""
+
+    for el in tree:
+        if el[0] == "python":
+            if el[1][0][:2] == "!!":
+                python += el[1][0][2:-2]
+            else:
+                python += el[1][0][1:] + u"\n"
+            continue
+        else:
+            if python:
+                execPython(python)
+                python = u""
+
+        try:
+            result += codegen(el)
+        except RuntimeError:
+            if included:
+                raise RuntimeError(u"in " + included + u":" + u(line))
+            else:
+                raise RuntimeError(u"in " + u(line))
+
+    if python:
+        execPython(python)
+
+    return result
+
+def finish(tree):
+    global first
+    first = True
+    return _finish(tree)
+
+ymlFunc["_parentheses"] = YF("parms")
+ymlFunc["_parm"] = YF("parm")
+ymlFunc["_generic"] = YF("generic")
+ymlFunc["_base"] = YF("base")