protected void BuildHelpers()
{
_weightTotalsByNonterminal = Cache.Create(() => Helpers.BuildLookup(
() => this.Productions,
(p) => p.Lhs,
(p) => p.Weight,
() => new Boxed <double>(0.0),
(x, y) => x.Value += y
));
this.Caches.Add(_weightTotalsByNonterminal);
_nonterminals = Cache.Create(() => {
var hs = new HashSet <Nonterminal>();
hs.Add(Start);
foreach (var production in this.Productions)
{
hs.Add(production.Lhs);
foreach (var word in production.Rhs)
{
var nonterminal = word as Nonterminal;
if (nonterminal != null)
{
hs.Add(nonterminal);
}
}
}
return((ISet <Nonterminal>)hs);
});
this.Caches.Add(_nonterminals);
_terminals = Cache.Create(() => {
var hs = new HashSet <Terminal>();
foreach (var production in this.Productions)
{
foreach (var word in production.Rhs)
{
var terminal = word as Terminal;
if (terminal != null)
{
hs.Add(terminal);
}
}
}
return((ISet <Terminal>)hs);
});
this.Caches.Add(_terminals);
_nullableDict = Cache.Create(() => GrammarHelpers.GetNullable(new HashSet <Production>(Productions)));
this.Caches.Add(_nullableDict);
}
public Grammar(IEnumerable <Production> productions, Nonterminal start) : base(start)
{
_productions = new List <Production>(productions);
// if (simplify) {
SimplifyWithoutInvalidate();
//}
_table = Cache.Create(() => Helpers.BuildLookup(
() => _productions,
(p) => p.Lhs,
(p) => p,
() => (ICollection <Production>) new List <Production>(),
(x, y) => x.Add(y)
));
this.Caches.Add(_table);
BuildHelpers();
}
private void BuildLookups()
{
_reverseTerminalProductions = Cache.Create(() => Helpers.BuildLookup(
() => _terminalProductions,
(p) => (Terminal)p.Rhs[0],
(p) => p,
() => (ICollection <Production>) new HashSet <Production>(),
(x, y) => x.Add(y)
));
this.Caches.Add(_reverseTerminalProductions);
_ntProductionsByNonterminal = Cache.Create(() => Helpers.BuildLookup(
() => _nonterminalProductions,
(p) => p.Lhs,
(p) => p,
() => (ICollection <Production>) new HashSet <Production>(),
(x, y) => x.Add(y)
));
this.Caches.Add(_ntProductionsByNonterminal);
_tProductionsByNonterminal = Cache.Create(() => Helpers.BuildLookup(
() => _terminalProductions,
(p) => p.Lhs,
(p) => p,
() => (ICollection <Production>) new HashSet <Production>(),
(x, y) => x.Add(y)
));
this.Caches.Add(_tProductionsByNonterminal);
_productionsFrom = Cache.Create(() => Helpers.BuildLookup(
() => _terminalProductions.Concat(_nonterminalProductions).Concat(_emptyProductions),
(p) => p.Lhs,
(p) => p,
() => (ICollection <Production>) new HashSet <Production>(),
(x, y) => x.Add(y)
));
this.Caches.Add(_productionsFrom);
}
public static Cache <T> Create <T>(Func <T> build)
{
return(Cache <T> .Create(build));
}