MTS 8: LISP and SLIP in MTS
June 1976
┌──────────────────────────────────────────────────────────────┐ ┌ ┌
| | Original New | Original New |
| Original | list list | list list |
| | changed with | changed with |
| List | after new | after new |
| | NULSTR Header | NULSTL Header |
|────────────┼────────────────────────┼────────────────────────| ┌ ┘
| ┌────────┐ | ┌────────┐ ┌────────┐ | ┌────────┐ ┌────────┐ |
| | | | | | | | | | | | | |
| | HEADER | | | HEADER | | HEADER | | | HEADER | | HEADER | |
| | | | | | | | | | | | | |
| └────────┘ | └────────┘ └────────┘ | └────────┘ └────────┘ |
| | | |
| ┌────────┐ | ┌────────┐ | ┌────────┐ |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| |────────| | └────────┘ ┌────────┐ | |────────| | ┌ ┘ ┌ ┘
| | | | | | | | | |
| | | | | | | | | |
| |────────| | |────────| | ┌────────┐ └────────┘ | ┌ ┘ ┌ ┘
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| └────────┘ | └────────┘ | └────────┘ |
| | | |
└──────────────────────────────────────────────────────────────┘ ┘ ┘
Figure 1: The Result of NULSTR and NULSTL Operations
The function
LSTEQL(LST1, LST2)
compares two list structures with aliases LST1 and LST2. If the two are
identical in structure and content, the returned value is 0; otherwise
it is -1. Description Lists and List Marks (see the subsection "List
Marks and Description Lists") are not compared.
The function
LSSCPY(LST)
creates a copy of the list structure with alias LST. Its returned value
is the name of the new list structure. Description Lists and List Marks
are not copied.
The function
126 SLIP

MTS 8: LISP and SLIP in MTS
June 1976
LISTMT(LST)
tests whether the list with alias LST is empty. If so, it delivers 0
value; otherwise it delivers -1. Note that an empty list can have a
nonempty Description List.
The following functions return cell names.
MADLFT(CADR)
and
MADRGT(CADR)
yield the names of the cell to the left and right, respectively, of the
one specified in the argument. The value is returned in INTEGER mode.
If it refers to the Header the SLIP name format is used. If the integer
input argument is the cell name of a Header of a list, the names of the
bottom and top cells, respectively, are obtained.
For this version of SLIP two functions CADLFT and CADRGT whose
purpose is similar to the above have been added.
CADLFT(CADR,IFLAG)
and
CADRGT(CADR,IFLAG)
yield the names of the cell to the left and right, respectively, of the
one specified in the argument. The value is always in INTEGER mode. If
the value refers to the Header, IFLAG is -1, otherwise IFLAG is 0.
Therefore, for example
DAT = DATUM(MADRGT(LST))
or
DAT = DATUM(CADRGT(LST,IFLAG))
and
DAT = TOP(LST)
are equivalent.
MADNTP(LST,N)
and
MADNBT(LST,N)
SLIP 127