A read-only interface for objects that act as Loyc trees. More...
Source file:
Remarks
A read-only interface for objects that act as Loyc trees.
To simplify implementations of this interface, there is no separate list of attributes and arguments; ILNode itself acts as a list of child nodes. The argument list is numbered from 0 to Max, so the number of arguments is Max + 1 (which is what the ArgCount() extension method returns).
A node with no children must report Min = -1 and Max = -2, or some extension methods will malfunction.
You can think of any node N as having a single contiguous list of child nodes indexed from N.Min to N.Max. Items with non-negative indexes (e.g. N[0], N[1]) are arguments; N[-1] is an alias for Target; and indexes below -1 refer to attributes (e.g. N[-2] is the last attribute in the attribute list)
ArgCount() and AttrCount() are implemented as extension methods; they return Max + 1 and -Min - 1 respectively (note: ArgCount() is different from LNode.ArgCount in case Kind != LNodeKind.Call: ArgCount() returns -1 in that case while LNode.ArgCount reurns zero.
The IsId(), IsLiteral() and IsCall() extension methods are useful shorthand for testing the Kind property.
The Attrs() and Args() extension methods return slices of this node corresponding to the attributes and arguments.
Tip: the LES node printer can print any ILNode as a string. See Loyc.Syntax.Les.Les3LanguageService.Print(ILNode, StringBuilder, IMessageSink, ParsingMode, ILNodePrinterOptions)
Properties | |
| LNodeKind | Kind [get] |
| Symbol | Name [get] |
| ILNode | Target [get] |
| ISourceRange | Range [get] |
| NodeStyle | Style [get, set] |
 Properties inherited from Loyc.Syntax.IUninterpretedLiteral | |
| UString | TextValue [get] |
| Represents the serialized text of the value. More... | |
| Symbol | TypeMarker [get] |
| Represents the type of the value. More... | |
| Properties inherited from Loyc.IHasValue< object > | |
| T | Value [get] |
| Properties inherited from Loyc.Collections.INegListSource< ILNode > | |
| int | Min [get] |
| Returns the minimum valid index in the collection. More... | |
| int | Max [get] |
| Returns the maximum valid index in the collection. More... | |
| Properties inherited from Loyc.IHasLocation | |
| object | Location [get] |
Public Member Functions | |
| bool | CallsMin (Symbol name, int argCount) |
Returns true if Kind == LNodeKind.Call, Name == name, and Max + 1 >= argCount. More... | |
| bool | Calls (Symbol name, int argCount) |
Returns true if Name == name and Max + 1 == argCount (which implies Kind == LNodeKind.Call if argCount != -1). More... | |
| Public Member Functions inherited from Loyc.Collections.INegListSource< ILNode > | |
| IRange< T > | Slice (int start, int count=int.MaxValue) |
| Returns a sub-range of this list. More... | |
Member Function Documentation
◆ Calls()
| bool Loyc.Syntax.ILNode.Calls | ( | Symbol | name, |
| int | argCount | ||
| ) |
Returns true if Name == name and Max + 1 == argCount (which implies Kind == LNodeKind.Call if argCount != -1).
This could have been an extension method, but when verifying that you have a certain kind of node, it's common to check both the Name and ArgCount(); checking both in one call avoids extra interface invocations.
Implemented in Loyc.Syntax.LNode, and Loyc.Syntax.CallNode.
◆ CallsMin()
| bool Loyc.Syntax.ILNode.CallsMin | ( | Symbol | name, |
| int | argCount | ||
| ) |
Returns true if Kind == LNodeKind.Call, Name == name, and Max + 1 >= argCount.
- See also
- LNodeExt.Calls
Implemented in Loyc.Syntax.LNode, and Loyc.Syntax.CallNode.
