public CfgLL1ParseTable ToLLkParseTable()
{
// Here we populate the outer dictionary with one non-terminal for each key
// we populate each inner dictionary with the result terminals and associated
// rules of the predict tables except in the case where the predict table
// contains null. In that case, we use the follows to get the terminals and
// the rule associated with the null predict in order to compute the inner
// dictionary. The conflict resolution tables are created as needed. Basically
// they are nested parse tables for additional lookahead resolution.
// The parser can use these to further resolve conflicts.
var predict = FillPredict();
var follows = FillFollows();
var result = new CfgLL1ParseTable();
foreach (var nt in _EnumNonTerminals())
{
var d = new Dictionary <string, CfgLL1ParseTableEntry>();
foreach (var f in predict[nt])
{
if (null != f.Symbol)
{
CfgLL1ParseTableEntry or;
if (d.TryGetValue(f.Symbol, out or))
{
if (null != or.ConflictTable)
{
}
else if (null != or.Rule)
{
var pt = new CfgLL1ParseTable();
var dd = new Dictionary <string, CfgRule>();
throw new CfgException(
string.Format(
"FIRST FIRST conflict between {0} and {1} on {2}",
or.Rule,
f.Rule,
f.Symbol));
}
}
else
{
or.ConflictTable = null;
or.Rule = f.Rule;
d.Add(f.Symbol, or);
}
}
else
{
var ff = follows[nt];
foreach (var fe in ff)
{
CfgLL1ParseTableEntry or;
if (d.TryGetValue(fe, out or))
{
// we can override conflict handling with the followsConflict
// attribute. If specified (first/last/error - error is default) it will choose
// the first or last rule respectively.
var fc = AttributeSets.GetAttribute(nt, "followsConflict", "error") as string;
if ("error" == fc)
{
throw new CfgException(
string.Format(
"FIRST FOLLOWS conflict between {0} and {1} on {2}",
or.Rule,
f.Rule,
fe));
}
else if ("last" == fc)
{
d[fe] = new CfgLL1ParseTableEntry(f.Rule);
}
}
else
{
d.Add(fe, new CfgLL1ParseTableEntry(f.Rule));
}
}
}
}
result.Add(nt, d);
}
return(result);
}
public CfgLL1ParseTable ToLL1ParseTable()
{
// Here we populate the outer dictionary with one non-terminal for each key
// we populate each inner dictionary with the result terminals and associated
// rules of the predict tables except in the case where the predict table
// contains null. In that case, we use the follows to get the terminals and
// the rule associated with the null predict in order to compute the inner
// dictionary. The conflict resolution tables are always empty for LL(1)
var predict = FillPredict();
var follows = FillFollows();
var exmsgs = new List <CfgMessage>();
var result = new CfgLL1ParseTable();
foreach (var nt in _EnumNonTerminals())
{
var d = new Dictionary <string, CfgLL1ParseTableEntry>();
foreach (var f in predict[nt])
{
if (null != f.Symbol)
{
CfgLL1ParseTableEntry re;
re.ConflictTable = null;
re.Rule = f.Rule;
CfgLL1ParseTableEntry or;
if (d.TryGetValue(f.Symbol, out or))
{
exmsgs.Add(new CfgMessage(CfgErrorLevel.Error, 1,
string.Format(
"FIRST FIRST conflict between {0} and {1} on {2}",
or.Rule,
f.Rule,
f.Symbol)));
}
else
{
d.Add(f.Symbol, re);
}
}
else
{
var ff = follows[nt];
foreach (var fe in ff)
{
CfgLL1ParseTableEntry or;
if (d.TryGetValue(fe, out or))
{
// we can override conflict handling with the followsConflict
// attribute. If specified (first/last/error - error is default) it will choose
// the first or last rule respectively.
var fc = AttributeSets.GetAttribute(nt, "followsConflict", "error") as string;
if ("error" == fc)
{
exmsgs.Add(new CfgMessage(CfgErrorLevel.Error, 2,
string.Format(
"FIRST FOLLOWS conflict between {0} and {1} on {2}",
or.Rule,
f.Rule,
fe)));
}
else if ("last" == fc)
{
d[fe] = new CfgLL1ParseTableEntry(f.Rule);
}
}
else
{
d.Add(fe, new CfgLL1ParseTableEntry(f.Rule));
}
}
}
}
result.Add(nt, d);
}
CfgException.ThrowIfErrors(exmsgs);
return(result);
}