Datatype Context
[Urlan Datatype System]

Contexts are a table of word/value pairs. More...


Defines
#define	ur_ctxCell(c, n) ((c)->ptr.cell + n)
	Get pointer of UCell in context by index.
Functions
UIndex	ur_makeContext (UThread *ut, int size)
	Generate and initialize a single context.
UBuffer *	ur_makeContextCell (UThread ut, int size, UCell cell)
	Generate a single context and set cell to reference it.
void	ur_ctxReserve (UBuffer *buf, int size)
	Allocates enough memory to hold size words.
UBuffer *	ur_ctxClone (UThread ut, const UBuffer src, UCell *cell)
	Clone a new context and set cell to reference it.
UBuffer *	ur_ctxMirror (UThread ut, const UBuffer src, UCell *cell)
	Create a shallow copy of a context and set cell to reference the new context.
void	ur_ctxSetWords (UBuffer ctx, const UCell it, const UCell *end)
	Add the set-word! values in a series of cells to the words in a context.
void	ur_ctxInit (UBuffer *buf, int size)
	Initialize context buffer.
void	ur_ctxFree (UBuffer *buf)
	Free context data.
int	ur_atomsSearch (const UAtomEntry *entries, int count, UAtom atom)
	Find an atom in a UAtomEntry table using a binary search.
int	ur_ctxLookupNoSort (const UBuffer *ctx, UAtom atom)
	Find word in context by atom.
int	ur_ctxAppendWord (UBuffer *ctx, UAtom atom)
	Append word to context.
int	ur_ctxAddWordI (UBuffer *ctx, UAtom atom)
	Add word to context if it does not already exist.
UCell *	ur_ctxAddWord (UBuffer *ctx, UAtom atom)
	Similar to ur_ctxAddWordI(), but safely returns the cell pointer.
void	ur_atomsSort (UAtomEntry *entries, int low, int high)
	Perform quicksort on UAtomEntry table.
UBuffer *	ur_ctxSort (UBuffer *ctx)
	Sort the internal context search table so ur_ctxLookup() can be used.
const UBuffer *	ur_sortedContext (UThread ut, const UCell cell)
	Get context and make sure it is ready for ur_ctxLookup().
int	ur_ctxLookup (const UBuffer *ctx, UAtom atom)
	Find word in context by atom.
void	ur_bindCells (UThread ut, UCell it, UCell end, const UBindTarget bt)
	Bind an array of cells to a target.
void	ur_bind (UThread ut, UBuffer blk, const UBuffer *ctx, int bindType)
	Bind block to context.
void	ur_infuse (UThread ut, UCell it, UCell end, const UBuffer ctx)
	Replace words in cells with their values from a context.

Detailed Description

Contexts are a table of word/value pairs.

Function Documentation

int ur_atomsSearch	(	const UAtomEntry *	entries,
		int	count,
		UAtom	atom
	)

Find an atom in a UAtomEntry table using a binary search.

The table must have been previously sorted with ur_atomsSort().

Returns:: Index of atom in table or -1 if not found.

void ur_atomsSort	(	UAtomEntry *	entries,
		int	low,
		int	high
	)

Perform quicksort on UAtomEntry table.

Pass low of 0 and high of (count - 1) to sort the entire table.

Parameters:

	entries	Array of initialized UAtomEntry structs.
	low	First entry in sort partition.
	high	Last entry in sort partition.

void ur_bind	(	UThread *	ut,
		UBuffer *	blk,
		const UBuffer *	ctx,
		int	bindType
	)

Bind block to context.

This recursively binds all sub-blocks.

Parameters:

	blk	Block to bind.
	ctx	Context. This may be a stand-alone context outside of any dataStore.
	bindType	UR_BIND_THREAD, UR_BIND_ENV, etc.

Examples:: calculator.c.

void ur_bindCells	(	UThread *	ut,
		UCell *	it,
		UCell *	end,
		const UBindTarget *	bt
	)

Bind an array of cells to a target.

This recursively binds all blocks in the range of cells.

Parameters:

	it	First cell.
	end	End of cell array.
	bt	Bind target.

UCell* ur_ctxAddWord	(	UBuffer *	ctx,
		UAtom	atom
	)

Similar to ur_ctxAddWordI(), but safely returns the cell pointer.

Returns:: Pointer to value cell of word.

Examples:: calculator.c.

int ur_ctxAddWordI	(	UBuffer *	ctx,
		UAtom	atom
	)

Add word to context if it does not already exist.

If added, the word is initialized as unset.

Note that the ctx->ptr may be changed by this function.

Returns:: Index of word in context.

See also:: ur_ctxAppendWord

int ur_ctxAppendWord	(	UBuffer *	ctx,
		UAtom	atom
	)

Append word to context.

This should only be called if the word is known to not already exist in the context.

The new word is initialized as unset.

Returns:: Index of word in context.

See also:: ur_ctxAddWordI, ur_ctxAddWord

UBuffer* ur_ctxClone	(	UThread *	ut,
		const UBuffer *	src,
		UCell *	cell
	)

Clone a new context and set cell to reference it.

Parameters:

	src	Context to copy.
	cell	Cell to initialize.

Returns:: Pointer to context buffer.

void ur_ctxFree ( UBuffer * buf )

Free context data.

buf->ptr and buf->used are set to zero.

void ur_ctxInit	(	UBuffer *	buf,
		int	size
	)

Initialize context buffer.

Parameters:

size

Number of words to reserve.

int ur_ctxLookup	(	const UBuffer *	ctx,
		UAtom	atom
	)

Find word in context by atom.

The internal context search table must sorted with ur_ctxSort() or ur_sortedContext() before ur_ctxLookup is called.

Parameters:

	ctx	Initialized and sorted context buffer.
	atom	Atom of word to find.

Returns:: Word index or -1 if not found.

int ur_ctxLookupNoSort	(	const UBuffer *	ctx,
		UAtom	atom
	)

Find word in context by atom.

If the context is not sorted then a linear search will be done.

Parameters:

	cxt	Initialized context which has at least one word.
	atom	Atom of word to find.

Returns:: Word index or -1 if not found.

UBuffer* ur_ctxMirror	(	UThread *	ut,
		const UBuffer *	src,
		UCell *	cell
	)

Create a shallow copy of a context and set cell to reference the new context.

No binding is done, so any blocks remain bound to the source context.

Parameters:

	src	Context to copy.
	cell	Cell to initialize.

Returns:: Pointer to context buffer.

void ur_ctxReserve	(	UBuffer *	buf,
		int	size
	)

Allocates enough memory to hold size words.

buf->used is not changed.

Parameters:

	buf	Initialized context buffer.
	size	Number of words to reserve.

void ur_ctxSetWords	(	UBuffer *	ctx,
		const UCell *	it,
		const UCell *	end
	)

Add the set-word! values in a series of cells to the words in a context.

Parameters:

	ctx	Destination context.
	it	Start of cells.
	end	End of cells.

UBuffer* ur_ctxSort ( UBuffer * ctx )

Sort the internal context search table so ur_ctxLookup() can be used.

If the context is already sorted then nothing is done. Each time new words are appended to the context it will become un-sorted.

Parameters:

ctx

Initialized context buffer.

Returns:: The ctx argument.

Examples:: calculator.c.

void ur_infuse	(	UThread *	ut,
		UCell *	it,
		UCell *	end,
		const UBuffer *	ctx
	)

Replace words in cells with their values from a context.

This recursively infuses all sub-blocks.

Unlike bind, this only modifies UT_WORD cells in UT_BLOCK or UT_PAREN slices.

Parameters:

	bi	Cells to infuse.
	ctx	Context.

UIndex ur_makeContext	(	UThread *	ut,
		int	size
	)

Generate and initialize a single context.

If you need multiple buffers then ur_genBuffers() should be used.

Parameters:

size

Number of words to reserve.

Returns:: Buffer id of context.

UBuffer* ur_makeContextCell	(	UThread *	ut,
		int	size,
		UCell *	cell
	)

Generate a single context and set cell to reference it.

If you need multiple buffers then ur_genBuffers() should be used.

Parameters:

	size	Number of words to reserve.
	cell	Cell to initialize.

Returns:: Pointer to context buffer.

const UBuffer* ur_sortedContext	(	UThread *	ut,
		const UCell *	cell
	)

Get context and make sure it is ready for ur_ctxLookup().

If the context is shared and has not been sorted, then an error is generated with ur_error() and zero is returned.

Parameters:

cell

Valid context cell.

Returns:: Pointer to context buffer or zero.

Generated on 27 Jan 2012 by Doxygen 1.5.1

Datatype Context [Urlan Datatype System]

Defines

Functions

Detailed Description

Function Documentation

Datatype Context
[Urlan Datatype System]