# Dot Functions

> [HTML Version](dotfunctions.htm)

_Reorganized August 2025_

Like [Dot Variables](dotvariables.htm.md), Dot Functions are so named because they begin with a period (dot). There is no particular significance to the dot, other than to minimize conflicts with existing variables or functions when adding new system functions to ASB. For example, when the .EXTENT() function was added, the dot prefix was chosen to avoid potential conflict with existing arrays or user-defined functions named EXTENT. In the case of the .INSTRR() function, the dot prefix was chosen to create more separation with the similarly named INSTR() function.

Dot functions fall into various categories, as shown below.

**Collections and Arrays**

•	[Multi-level List MLIST](multi-level_list_mlist.htm.md)

•	[Special ORDMAP Functions](specialordmapfunctions.htm.md)

•	[.EXTENT()](extent().htm.md)

**String**

•	[.INSTRR()](instrr().htm.md)

•	[.ISEMPTY()](isempty().htm.md)

**Print File Processing**

•	[.LINENO()](lineno()_pageno().htm.md)

•	[.PAGENO()](lineno()_pageno().htm.md)

**Random and ISAM File  File Processing**

•	[.FSTAT()](filefunctions.htm.md)

•	[.RECNO()](filefunctions.htm.md)

•	.[RECSIZ()](filefunctions.htm.md)

**Defstruct Member Reference**

•	[.OFFSET()](offset().htm.md)

•	[.OFFSIZ\$()](offsiz$().htm.md)

**Function and Subroutine Support**

•	[.ARGTYP()](argtyp_and_argsiz().htm.md)

•	[.ARGSIZ()](argtyp_and_argsiz().htm.md)

•	[.EXTERN()](extern().htm.md)

•	[Implicit Function Return Value Capture](implicitfunctionreturn.htm.md)

**See Also**

•	[Dot Variables](dotvariables.htm.md)

•	[.CLEAR](clear_asb.htm.md) statement