private static AltRule createSubstitution(SymbolPosition position, string substSymbolName)
{
var code = new CodeBody().AddIdentifier("obj");
return(AltRule.CreateInternally(position, new RhsGroup[] {
RhsGroup.CreateSequence(position, RepetitionEnum.Once, new RhsSymbol(position, "obj", substSymbolName))
},
new CodeMix(CodeMix.SubstitutionComment).AddBody(code)));
}
private static AltRule createAppend(SymbolPosition position,
string lhsSymbolName,
IEnumerable <string> elementTypeNames,
params RhsSymbol[] symbols)
{
// if it does not exists it means we don't care about adding it
IEnumerable <RhsSymbol> named_symbols = symbols.Where(it => it.ObjName != null).ToArray();
string list_obj_name;
if (named_symbols.Count() == 1)
{
list_obj_name = "list";
}
else
{
list_obj_name = "tuple_list";
}
// since we are creating this code, the only conflict can come from symbol object names
list_obj_name = Grammar.RegisterName(list_obj_name, named_symbols.Select(it => it.ObjName).ToList());
var code = new CodeBody().AddSnippet("{");
if (named_symbols.Count() == 1)
{
code.AddWithIdentifier(list_obj_name, ".", "Add", "(", named_symbols.Single().ObjName, ");");
}
else
{
foreach (Tuple <RhsSymbol, int> sym_pair in named_symbols.ZipWithIndex())
{
code.AddWithIdentifier(list_obj_name, ".", CodeWords.Item(sym_pair.Item2 + 1), ".", "Add", "(");
code.AddIdentifier(sym_pair.Item1.ObjName);
code.AddSnippet(");");
}
}
code.AddWithIdentifier("return", " ", list_obj_name, ";}");
return(AltRule.CreateInternally(position, new RhsGroup[] {
RhsGroup.CreateSequence(position, RepetitionEnum.Once, new RhsSymbol(position, list_obj_name, lhsSymbolName)),
RhsGroup.CreateSequence(position, RepetitionEnum.Once, symbols.Select(it => it.ShallowClone().SetSkip(false)).ToArray())
},
new CodeMix(CodeMix.AppendComment).AddBody(code)));
}
private IEnumerable <ProductionInfo> buildAltRule(string lhsSymbol, RecursiveEnum recursive,
AltRule alt, string treeNodeName)
{
// for each group assign a selector which enables/disables given symbols, to make all valid variations
// for example
// a -> X? [Y Z]
// is turned into (\ denotes disabled symbol)
// a -> \X Y \Z
// a -> \X \Y Z
// a -> X Y \Z
// a -> X \Y Z
IEnumerable <RhsEntitySelector> selectors = alt.RhsGroups.Select(it => new RhsEntitySelector(it)).ToArray();
while (true)
{
yield return(makeBuilderCall(lhsSymbol, recursive, alt, selectors.Select(it => it.BuildConfiguration()).Flatten().ToArray(), treeNodeName));
if (!selectors.Iterate())
{
break;
}
}
}
private ProductionInfo makeBuilderCall(string lhsSymbol,
RecursiveEnum recursive,
AltRule alt,
IEnumerable <SymbolMarked> symbolsMarked,
string treeNodeName)
{
// add production with no code
var prod_info = new ProductionInfo(alt.Position, lhsSymbol, recursive, symbolsMarked.Where(it => it.IsEnabled).Select(it => it.Symbol),
alt.MarkWith);
CodeBody code_body = null;
if (alt.Code != null)
{
code_body = (alt.Code as CodeMix).BuildBody(symbolsMarked.Where(sym => sym.Symbol.ObjName != null)
.Select(sym => sym.Symbol.GetCodeArgumentNames().Select(it => Tuple.Create(it, sym.IsEnabled))).Flatten())
.Trim();
string identity_function_on = null;
// are we just passing one of the parameters?
if (code_body.IsIdentity)
{
identity_function_on = code_body.IdentityIdentifier;
}
foreach (string var_name in code_body.GetVariables())
{
SymbolMarked sym = symbolsMarked
.Where(sm => sm.Symbol.GetCodeArgumentNames().Contains(var_name))
// there could be duplicates so we "prefer" enabled element
.OrderBy(it => it.IsEnabled ? 0 : 1)
.FirstOrDefault();
if (sym != null)
{
sym.IsParamUsed = true;
}
}
var anon_args = new Dictionary <SymbolMarked, string>();
foreach (Tuple <SymbolMarked, int> sym_pair in symbolsMarked.ZipWithIndex())
{
if (sym_pair.Item1.Symbol.ObjName == null)
{
anon_args.Add(sym_pair.Item1, code_body.RegisterNewIdentifier("_" + sym_pair.Item2));
}
}
IEnumerable <SymbolMarked> arg_symbols = symbolsMarked.Where(it => it.IsEnabled || it.IsParamUsed).ToList();
// build external function to run the user code
string func_ref = registerLambda(lhsSymbol,
arg_symbols.Select(sym => sym.Symbol.GetCodeArgumentTypes(grammar)).Flatten(),
grammar.TreeNodeName,
arg_symbols.Select(sym => sym.Symbol.GetCodeArgumentNames()
.Select(it => Tuple.Create(it, anon_args.GetOrNull(sym)))).Flatten(),
code_body);
// build a lambda with call to a just built function
// note that our lambda can have fewer arguments than the actual fuction
// in such case we pass "nulls" for disabled arguments
// we add nulls to params in order to keep track which arguments comes from which parameters
IEnumerable <FuncParameter> lambda_params = arg_symbols.Where(it => it.IsEnabled)
.Select(it => FuncParameter.Create(it.Symbol.ObjName, anon_args.GetOrNull(it), grammar.GetTypeNameOfSymbol(it.Symbol))).ToArray();
// if the code indicates that this is identity function, then just find out which parameter is passed along
if (identity_function_on != null)
{
// we can fail for two reasons here:
// (1) ok -- single variable we found in the code body is not a parameter, but global variable
// (2) BAD -- we have case of unpacking the data, and that case so far we cannot handle
// ad.2) consider such rule as
// x -> (a b)+ { b };
// "a" and "b" will be handled as tuple of lists
// so in entry function we will get a tuple, and then we will call actuall user action code
// some "__function_13__(a,b)" which returns the "b"
// so we could compute index for inner parameter (for "b" it is 1)
// but we cannot compute index for outer function, because there is no index for "b" at all
// there is only one parameter -- tuple -- holding "a" (in Item1) and "b" (in Item2) at the same time
// so if anything we would have to introduce some combo index:
// outer index --> optional unpacking index --> inner index
// too much trouble for now
Option <int> index = lambda_params.Select(it => it.Name)
.ZipWithIndex().Where(it => it.Item1 == identity_function_on).Select(it => it.Item2).OptSingle();
if (index.HasValue)
{
prod_info.IdentityOuterFunctionParamIndex = index.Value;
}
}
prod_info.ActionCode = CodeLambda.CreateProxy(
lhsSymbol,
// lambda arguments
lambda_params,
treeNodeName,
func_ref,
arg_symbols.Select(arg => arg.Symbol.CombinedSymbols == null
// regular symbols
? new[] { new CodeBody().AddIdentifier(arg.IsEnabled ? (arg.Symbol.ObjName ?? anon_args[arg]) : CodeWords.Null) }
// compound symbols, we have to use embedded atomic symbols instead now
: arg.Symbol.UnpackTuple(arg.IsEnabled)
)
.Flatten());
prod_info.CodeComment = alt.Code.Comment;
}
return(prod_info);
}
private AltRule createSeed(SymbolPosition position,
List <Production> productions,
bool doubled, // should we double the seed right at the start
string lhsSymbolName,
IEnumerable <string> elementTypeNames,
params RhsSymbol[] symbols)
{
RhsSymbol[] init_symbols = symbols.Where(it => !it.SkipInitially).ToArray();
var main_code = new CodeBody().AddWithIdentifier(CodeWords.New, " ");
main_code.Append(makeTupleListCode(position, elementTypeNames));
main_code.AddSnippet("(");
IEnumerable <CodeBody> code_lists
= elementTypeNames.Select(it => new CodeBody().AddWithIdentifier(CodeWords.New, " ", CodeWords.List, "<", it, ">{")).ToList();
// purpose: to handle names in doubled seed mode
Dictionary <RhsSymbol, string[]> obj_name_substs = new Dictionary <RhsSymbol, string[]>();
{
IEnumerable <RhsSymbol> named_symbols = symbols.Where(it => it.ObjName != null);
if (named_symbols.Any())
{
foreach (Tuple <RhsSymbol, CodeBody> tuple in named_symbols.SyncZip(code_lists))
{
RhsSymbol nsymbol = tuple.Item1;
CodeBody lcode = tuple.Item2;
bool double_sym = doubled && !nsymbol.SkipInitially;
string[] name_subst = new string[double_sym ? 2 : 1];
obj_name_substs.Add(nsymbol, name_subst);
// if we double the element, we have to come up with new names
if (double_sym)
{
name_subst[0] = AutoNames.Double1 + nsymbol.ObjName + "__";
name_subst[1] = AutoNames.Double2 + nsymbol.ObjName + "__";
}
else
{
name_subst[0] = nsymbol.ObjName;
}
for (int i = 0; i < (double_sym ? 2 : 1); ++i)
{
if (i == 1)
{
lcode.AddSnippet(",");
}
if (double_sym)
{
lcode.AddIdentifier(name_subst[i]);
}
else
{
lcode.AddIdentifier(nsymbol.ObjName);
}
}
}
}
}
foreach (Tuple <CodeBody, int> code_pair in code_lists.ZipWithIndex())
{
code_pair.Item1.AddSnippet("}");
if (code_pair.Item2 > 0)
{
main_code.AddSnippet(",");
}
main_code.Append(code_pair.Item1);
}
main_code.AddSnippet(")");
// in case of doubled seed we have to rename the symbols
// otherwise just make shallow copies without renaming
// but since we already set proxy name correctly, we can use shared code for both cases
var seed_symbols = new LinkedList <RhsSymbol>();
for (int i = 0; i < (doubled ? 2 : 1); ++i)
{
foreach (RhsSymbol sym in (i == 0 ? init_symbols : symbols))
{
if (sym.ObjName == null)
{
seed_symbols.AddLast(sym.ShallowClone());
}
else
{
int s_idx = (i == 1 && sym.SkipInitially) ? 0 : i;
seed_symbols.AddLast(sym.Renamed(obj_name_substs[sym][s_idx]));
}
}
}
return(AltRule.CreateInternally(position,
// are there any symbols for production
seed_symbols.Any()
? new RhsGroup[] { RhsGroup.CreateSequence(position, RepetitionEnum.Once, seed_symbols.Select(it => it.SetSkip(false)).ToArray()) }
: new RhsGroup[] { },
new CodeMix(CodeMix.SeedComment).AddBody(main_code)));
}
