/// <summary>
/// Parse given input string in the concrete grammar.
/// </summary>
/// <param name="str">Input string to be parsed.</param>
/// <param name="cat">Category (Type) to parse.</param>
/// <param name="heuristics">Heuristic (see the GF C runtime docs).</param>
/// <param name="Callback1">Callback function.</param>
/// <param name="Callback2">Callback function.</param>
/// <returns>Enumerates pairs of (abstract grammar) expressions and corresponding probability.</returns>
public IEnumerable <Tuple <Expression, float> > Parse(string str, Type cat = null, double?heuristics = null,
Action Callback1 = null, Action Callback2 = null)
{
var parse_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(parse_pool);
cat = cat ?? Grammar.StartCat;
using (var nativeStr = new Native.NativeString(str))
{
var result_pool = new NativeGU.NativeMemoryPool();
var callbackMap = Native.pgf_new_callbacks_map(this.Ptr, parse_pool.Ptr);
var iterator = Native.pgf_parse_with_heuristics(this.Ptr, cat.Ptr,
nativeStr.Ptr, heuristics ?? -1, callbackMap,
exn.Ptr, parse_pool.Ptr, result_pool.Ptr);
if (iterator == IntPtr.Zero || exn.IsRaised)
{
throw new PGF.Exceptions.ParseErrorException();
}
else
{
foreach (var ptr in NativeGU.IteratorToIEnumerable(iterator, parse_pool.Ptr))
{
var exprProb = (Native.PgfExprProb)Marshal.PtrToStructure(ptr, typeof(Native.PgfExprProb));
yield return(Tuple.Create(Expression.FromPtr(exprProb.expr, result_pool),
exprProb.prob));
}
}
}
}
/// <summary>
/// Get the bracketed (structured) linearization of an expression.
/// </summary>
/// <param name="e"></param>
/// <returns></returns>
public Bracket BracketedLinearize(Expression e)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var cts = Native.pgf_lzr_concretize(Ptr, e.Ptr, exn.Ptr, tmp_pool.Ptr);
var ctree = IntPtr.Zero;
NativeGU.gu_enum_next(cts, ref ctree, tmp_pool.Ptr);
if (ctree == IntPtr.Zero)
{
return(null);
}
ctree = Native.pgf_lzr_wrap_linref(ctree, tmp_pool.Ptr);
var builder = new Bracket.BracketBuilder();
var mem = Marshal.AllocHGlobal(Marshal.SizeOf <Native.PgfLinFuncs>());
Marshal.StructureToPtr <Native.PgfLinFuncs>(builder.LinFuncs, mem, false);
Native.pgf_lzr_linearize(Ptr, ctree, 0, ref mem, tmp_pool.Ptr);
var b = builder.Build();
Marshal.FreeHGlobal(mem);
return(b);
}
/// <summary>
/// Read grammar from PGF file.
/// </summary>
/// <param name="fn">filename</param>
/// <returns></returns>
public static Grammar FromFile(string fn)
{
var obj = new Grammar();
var exn = new NativeGU.NativeExceptionContext(new NativeGU.NativeMemoryPool());
obj.pool = new NativeGU.NativeMemoryPool();
obj._ptr = Native.pgf_read(fn, obj.pool.Ptr, exn.Ptr);
if (exn.IsRaised)
{
throw new PGF.Exceptions.PGFException($"Could not read PGF from file {fn}. ({System.IO.Directory.GetCurrentDirectory()})");
}
return(obj);
}
/// <summary>
/// Get all possible linearization for an expression (see <see cref="Linearize(Expression)"/>).
/// </summary>
/// <param name="e"></param>
/// <returns></returns>
public IEnumerable <string> LinearizeAll(Expression e)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var cts = Native.pgf_lzr_concretize(Ptr, e.Ptr, exn.Ptr, tmp_pool.Ptr);
if (exn.IsRaised || cts == IntPtr.Zero)
{
throw new PGF.Exceptions.PGFException("Could not linearize the abstract tree.");
}
return(NativeGU.IteratorToIEnumerable(cts, tmp_pool.Ptr).Select(LinearizeCnc));
}
/// <summary>
/// Enumerate all expressions in the given category.
/// </summary>
/// <param name="cat"></param>
/// <returns></returns>
public IEnumerable <Expression> GenerateAll(Type cat = null)
{
cat = cat ?? StartCat;
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var result_pool = new NativeGU.NativeMemoryPool();
IntPtr ptr = IntPtr.Zero;
var iterator = Native.pgf_generate_all(this._ptr, cat.Ptr, exn.Ptr, tmp_pool.Ptr, result_pool.Ptr);
return(NativeGU.IteratorToIEnumerable(iterator, tmp_pool.Ptr).Select(p =>
{
var exprProb = Marshal.PtrToStructure <Native.PgfExprProb>(ptr);
return Expression.FromPtr(exprProb.expr, result_pool);
}));
}
/// <summary>
/// Reduce expression.
/// </summary>
/// <param name="expr"></param>
/// <returns></returns>
public Expression Compute(Expression expr)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var result_pool = new NativeGU.NativeMemoryPool();
var newExpr = Native.pgf_compute(_ptr, expr.Ptr, exn.Ptr, pool.Ptr, result_pool.Ptr);
if (exn.IsRaised || newExpr == IntPtr.Zero)
{
throw new PGF.Exceptions.PGFException("Could not reduce expression.");
}
else
{
return(Expression.FromPtr(newExpr, result_pool));
}
}
/*
* [StructLayout(LayoutKind.Sequential)]
* public struct PGFClosure
* {
* public GuMapItor fn;
* public IntPtr grammar;
* public IntPtr obj;
* }*/
public static string ReadString(Action <IntPtr, NativeGU.NativeExceptionContext> f)
{
var pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(pool);
var sbuf = NativeGU.gu_new_string_buf(pool.Ptr);
var output = NativeGU.gu_string_buf_out(sbuf);
f(output, exn);
if (exn.IsRaised)
{
throw new Exception();
}
var strPtr = NativeGU.gu_string_buf_freeze(sbuf, pool.Ptr);
var str = Native.NativeString.StringFromNativeUtf8(strPtr);
return(str);
}
public static void MapIter(MapIterFunc iter, IntPtr _pgf, Action <string, IntPtr> action)
{
var pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(pool);
var f = new GuMapItor()
{
fn = (self, key, value, _err) =>
{
action(Native.NativeString.StringFromNativeUtf8(key), value);
if (exn.IsRaised)
{
throw new Exception();
}
}
};
iter(_pgf, ref f, exn.Ptr);
}
/// <summary>
/// Linearize expression, i.e. produce a string in the concrete grammar from an expression in the abstract grammar.
/// </summary>
/// <param name="e"></param>
/// <returns></returns>
public string Linearize(Expression e)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var buf = NativeGU.gu_new_string_buf(tmp_pool.Ptr);
var out_ = NativeGU.gu_string_buf_out(buf);
Native.pgf_linearize(Ptr, e.Ptr, out_, exn.Ptr);
if (exn.IsRaised)
{
throw new PGF.Exceptions.PGFException();
}
else
{
var cstr = NativeGU.gu_string_buf_freeze(buf, tmp_pool.Ptr);
return(Native.NativeString.StringFromNativeUtf8(cstr));
}
}
private T Read <T>(Func <IntPtr, IntPtr, IntPtr, IntPtr> reader, Func <IntPtr, NativeGU.NativeMemoryPool, T> factory, string str)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var result_pool = new NativeGU.NativeMemoryPool();
using (var strNative = new Native.NativeString(str))
{
var in_ = NativeGU.gu_data_in(strNative.Ptr, strNative.Size, tmp_pool.Ptr);
var expr = reader(in_, result_pool.Ptr, exn.Ptr);
if (exn.IsRaised || expr == IntPtr.Zero)
{
throw new PGF.Exceptions.ParseErrorException();
}
else
{
return(factory(expr, result_pool));
}
}
}
private string LinearizeCnc(IntPtr cnc)
{
var tmp_pool = new NativeGU.NativeMemoryPool();
var exn = new NativeGU.NativeExceptionContext(tmp_pool);
var sbuf = NativeGU.gu_new_string_buf(tmp_pool.Ptr);
var out_ = NativeGU.gu_string_buf_out(sbuf);
var wrapped = Native.pgf_lzr_wrap_linref(cnc, tmp_pool.Ptr);
Native.pgf_lzr_linearize_simple(Ptr, wrapped, 0, out_, exn.Ptr, tmp_pool.Ptr);
if (exn.IsRaised)
{
throw new PGF.Exceptions.PGFException("Could not linearize abstract tree.");
}
var cstr = NativeGU.gu_string_buf_freeze(sbuf, tmp_pool.Ptr);
return(Native.NativeString.StringFromNativeUtf8(cstr));
}
