/// <summary> Creates a new {@link se.sics.prologbeans.PBTerm} instance representing a
/// list with the characters, as integer values, in the string argument as
/// its elements.
/// </summary>
/// <param name="value">the non-null value to represent
/// </param>
/// <returns> a term representing the argument
/// </returns>
static public PBTerm makeTerm(string value)
{
if (value == null)
{
throw new ArgumentNullException("value");
}
// [PM] 4.3.2
{
PBTerm tail = PBTerm.NIL;
for (int i = value.Length - 1; i >= 0; i--)
{
tail = PBTerm.makeTerm(PBTerm.makeTerm(value [i]), tail);
}
return(tail);
}
}
/// <summary> Adds the specified variable binding. The variable name must start
/// with an upper case letter or '_'.
/// </summary>
/// <param name="name">a prolog variable name
/// </param>
/// <param name="value">the value to bind to the variable
/// </param>
/// <returns> a reference to this <c>Bindings</c> object
/// </returns>
/// <exception cref="System.ArgumentException"> if the name is not a
/// valid prolog variable name
/// </exception>
public virtual Bindings bind(string name, float value)
{
return(bind(name, PBTerm.makeTerm(value)));
}
/*
* [PM] 4.1.3 Manage an explicit stack to avoid running out of Java stack
* (SPRM 11909)
*/
PBTerm parseTerm(System.IO.Stream stream)
{
Work outer = new Work(new PBTerm[1], null);
Work stack = outer;
do
{
int chr = stream.ReadByte();
PBTerm term;
if (FastParser.logging)
{
Console.Out.WriteLine("parseTerm() switch on " + chr);
}
switch (chr)
{
case INTEGER:
{
string val = getString(stream);
// return new PBInteger(val);
try {
term = new PBInteger(Convert.ToInt64(val, 10), val);
} catch (FormatException /* nfe */) {
// FIXME: Perhaps not catch FormatException? If malformed then it is no bignum either.
term = new PBBignum(BigInteger.Parse(val), val);
} catch (OverflowException) {
term = new PBBignum(BigInteger.Parse(val), val);
}
if (logging)
{
Console.Out.WriteLine("bump() INTEGER " + val);
}
stack = stack.bump(term);
}
break;
case FLOAT:
{
string val = getString(stream);
term = new PBFloat(Double.Parse(val), val);
if (logging)
{
Console.Out.WriteLine("bump() FLOAT " + val);
}
stack = stack.bump(term);
}
break;
case ATOM:
{
string val = getString(stream);
term = PBTerm.makeAtom(val);
if (logging)
{
Console.Out.WriteLine("bump() ATOM " + val);
}
stack = stack.bump(term);
}
break;
case VARIABLE:
{
string val = '_' + getString(stream);
if (variableTable == null)
{
variableTable = System.Collections.Hashtable.Synchronized(new System.Collections.Hashtable());
}
PBVariable var = (PBVariable)variableTable [val];
if (var == null)
{
var = new PBVariable(val);
variableTable [val] = var;
}
term = var;
if (logging)
{
Console.Out.WriteLine("bump() VARIABLE " + val);
}
stack = stack.bump(term);
}
break;
case STRING:
{
byte[] val = getBytes(stream);
PBTerm t = parseTerm(stream);
// Note that this builds the list from the end.
for (int i = val.Length - 1; i >= 0; i--)
{
t = PBTerm.makeTerm(new PBInteger(val [i]), t);
}
term = t;
if (logging)
{
Console.Out.WriteLine("bump() STRING " + val);
}
stack = stack.bump(term);
}
break;
case LIST:
{
const int noTerms = 2;
PBTerm[] terms = new PBTerm[noTerms];
term = new PBListCell(terms);
if (logging)
{
Console.Out.WriteLine("bump() LIST ./2");
}
stack = stack.bump(term, terms);
}
break;
case NIL:
{
term = PBTerm.NIL;
if (logging)
{
Console.Out.WriteLine("bump() NIL");
}
stack = stack.bump(term);
}
break;
case COMPOUND:
{
string val = getString(stream);
int noTerms = stream.ReadByte();
PBTerm[] terms = new PBTerm[noTerms];
term = PBTerm.makeTerm(val, terms);
if (logging)
{
Console.Out.WriteLine("bump() COMPOUND " + val + "/" + noTerms);
}
stack = stack.bump(term, terms);
}
break;
default:
throw new System.IO.IOException("Parse error: illegal character " + (char)chr);
}
} while (stack != null);
// assert outer != null;
// assert outer.args != null && outer.args.length == 1;
// assert validTerm(outer.args[0]);
if (logging)
{
Console.Out.WriteLine("parseTermWithStack returning " + outer.args [0]);
}
return(outer.args [0]);
}