Package convex.core.lang.ops

Class Let<T extends ACell>

java.lang.Object
convex.core.data.AObject
convex.core.data.ACell
convex.core.lang.AOp<T>
convex.core.lang.ops.AMultiOp<T>
convex.core.lang.ops.Let<T>
Type Parameters:
T - Result type of Op
All Implemented Interfaces:
IValidated, IWriteable
public class Let<T extends ACell> extends AMultiOp<T>
Op for executing a body after lexically binding one or more symbols. Can represent (let [..] ..) and (loop [..] ..). Loop version can act as a target for (recur ...) expressions.

  • Field Details

    • symbols

      protected final AVector<ACell> symbols
      Vector of binding forms. Can be destructuring forms

    • bindingCount

      protected final int bindingCount

    • isLoop

      protected final boolean isLoop

  • Constructor Details

  • Method Details

    • create

      public static <T extends ACell> Let<T> create(AVector<ACell> syms, AVector<AOp<ACell>> ops, boolean isLoop)

    • updateRefs

      public Let<T> updateRefs(IRefFunction func)
      Description copied from class: ACell
      Updates all Refs in this object using the given function. The function *must not* change the hash value of Refs, in order to ensure structural integrity of modified data structures. The implementation *should* re-attach any original encoding in order to prevent re-encoding or surplus hashing This is a building block for a very sneaky trick that enables use to do a lot of efficient operations on large trees of smart references. Must return the same object if no Refs are altered.
      Overrides:
      updateRefs in class AMultiOp<T extends ACell>
      Parameters:
      func - Ref update function
      Returns:
      Cell with updated Refs

    • getRefCount

      public int getRefCount()
      Description copied from class: ACell
      Gets the number of Refs contained within this Cell. This number is final / immutable for any given instance and is defined by the Cell encoding rules. WARNING: may not be valid id Cell is not canonical Contained Refs may be either external or embedded.
      Overrides:
      getRefCount in class AMultiOp<T extends ACell>
      Returns:
      The number of Refs in this Cell

    • getRef

      public final <R extends ACell> Ref<R> getRef(int i)
      Description copied from class: ACell
      Gets a numbered child Ref from within this Cell. WARNING: May be unreliable is cell is not canonical
      Overrides:
      getRef in class AMultiOp<T extends ACell>
      Type Parameters:
      R - Type of referenced Cell
      Parameters:
      i - Index of ref to get
      Returns:
      The Ref at the specified index

    • recreate

      protected Let<T> recreate(ASequence<AOp<ACell>> newOps)
      Description copied from class: AMultiOp
      Recreates this object with an updated list of child Ops.
      Specified by:
      recreate in class AMultiOp<T extends ACell>
      Returns:

    • recreate

      protected Let<T> recreate(ASequence<AOp<ACell>> newOps, AVector<ACell> newSymbols)

    • execute

      public Context execute(Context context)
      Description copied from class: AOp
      Executes this op with the given context. Must preserve depth unless an exceptional is returned.
      Specified by:
      execute in class AOp<T extends ACell>
      Parameters:
      context - Initial Context
      Returns:
      The updated Context after executing this operation

    • executeBody

      public Context executeBody(Context ctx)

    • print

      public boolean print(BlobBuilder bb, long limit)
      Description copied from class: AObject
      Prints this Object to a readable String Representation. SECURITY: Must halt and return false in O(1) time when limit of printing is exceeded otherwise DoS attacks may be possible.
      Specified by:
      print in class AObject
      Parameters:
      bb - BlobBuilder to append to. May be partially written if print limit exceeded
      limit - Limit of printing in string bytes
      Returns:
      True if fully printed within limit, false otherwise

    • opCode

      public byte opCode()
      Description copied from class: AOp
      Returns the opcode for this op
      Specified by:
      opCode in class AOp<T extends ACell>
      Returns:
      Opcode as a byte

    • encodeRaw

      public int encodeRaw(byte[] bs, int pos)
      Description copied from class: AOp
      Writes the raw data for this Op to the specified bytebuffer. Assumes Op tag and opcode already written.
      Overrides:
      encodeRaw in class AMultiOp<T extends ACell>
      Parameters:
      bs - Byte array to write to
      pos - Position to write in byte array
      Returns:
      The updated position

    • estimatedEncodingSize

      public int estimatedEncodingSize()
      Description copied from interface: IWriteable
      Estimate the encoded data size for this Cell. Used for quickly sizing buffers. Implementations should try to return a size that is highly likely to contain the entire object when encoded, including the tag byte. Should not traverse soft Refs, i.e. must be usable on arbitrary partial data structures
      Specified by:
      estimatedEncodingSize in interface IWriteable
      Overrides:
      estimatedEncodingSize in class AMultiOp<T extends ACell>
      Returns:
      The estimated size for the binary representation of this object.

    • read

      public static <T extends ACell> Let<T> read(Blob b, int pos, boolean isLoop) throws BadFormatException
      Read a Let Op from a Blob encoding
      Parameters:
      b - Blob to read from
      pos - Start position in Blob (location of tag byte)
      isLoop - Indicates if the Op should be considered a loop target
      Returns:
      New decoded instance
      Throws:
      BadFormatException - In the event of any encoding error