Datatype Path

Functions
UBuffer *	ur_makePathCell (UThread *ut, const UCell *nodes, int size, UCell *cell)
	Initialize path cell and generate block if needed.
int	ur_pathResolve (UThread *ut, UBlockIt *pi, UCell *tmp, UCell **lastCell)
	Get a pointer to the last value that a path! refers to.
int	ur_pathSelectCells (const UCell *selC, UCell *dest)
const UCell *	ur_pathSelect (UThread *ut, const UCell *selC, UCell *tmp, UCell **remain)
	Get a pointer to the last value that a select path! cell refers to.
UStatus	ur_setPath (UThread *ut, const UCell *path, const UCell *src)
	Set path.

Detailed Description

Function Documentation

ur_makePathCell()

UBuffer * ur_makePathCell	(	UThread *	ut,
		const UCell *	nodes,
		int	size,
		UCell *	cell )

Initialize path cell and generate block if needed.

The nodes & cell argument may point to the same UCell.

Parameters

nodes	Source cells starting with word!/lit-word!.
size	Number of path nodes to copy.
cell	Cell to initialize.

Returns

Pointer to block buffer or NULL if contained within UCellWord.

ur_pathResolve()

int ur_pathResolve	(	UThread *	ut,
		UBlockIt *	pi,
		UCell *	tmp,
		UCell **	lastCell )

Get a pointer to the last value that a path! refers to.

If the last path node is not a datatype that contains UCells then lastCell will be set to tmp.

Parameters

pi	Path iterator.
tmp	Cell to temporarily hold values for datatypes that don't contain UCells.
lastCell	Set to the address of the cell holding the last value in the path or tmp.

Returns

Type of the first node (UT_WORD or UT_GETWORD), or UR_THROW if path evaluation fails.

See also

ur_pathCell, ur_wordCell

ur_pathSelect()

const UCell * ur_pathSelect	(	UThread *	ut,
		const UCell *	selC,
		UCell *	tmp,
		UCell **	remain )

Get a pointer to the last value that a select path! cell refers to.

Parameters

tmp	Cell to temporarily hold values for datatypes that don't contain UCells.
remain	An expanded (UCell series) version of the remaining path is put at this address then the pointer is set to the end position. It must have enough space to hold two UCells.

Returns

Address of the cell holding the last value in the path (or tmp). NULL is returned if an error was thrown.

ur_pathSelectCells()

int ur_pathSelectCells	(	const UCell *	selC,
		UCell *	dest )

Parameters

dest	Cells to fill with path nodes. Must have enough space to hold three UCells.

Returns

Number of path nodes.

ur_setPath()

UStatus ur_setPath	(	UThread *	ut,
		const UCell *	path,
		const UCell *	src )

Set path.

This copies src into the cell which the path refers to.

If any of the path words are unbound (or bound to the shared environment) then an error is generated and UR_THROW is returned.

Parameters

path	Valid path cell.
src	Source value to copy.

Returns

UR_OK/UR_THROW