B. UNCONTROLLED REFERENCE WORDS
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APPENDIX B. UNCONTROLLED REFERENCE WORDS
The Uncontrolled Reference Word Set contains glossary definitions
which are included for public reference of words that have past
or present usage and/or are candidates for future
standardization. No recommendation is made that these words be
included in a system.
No restrictions are placed on the definition or usage of
uncontrolled words. However, use of these names for procedures
differing from the given definitions is discouraged.
!BITS 16b1 addr 16b2 -- "store-bits"
Store the value of 16b1 masked by 16b2 into the equivalent
masked part of the contents of addr, without affecting bits
outside the mask.
** n1 n2 -- n3 "power"
n3 is the value of n1 to the power n2.
+BLOCK w -- u "plus-block"
u is the sum of w plus the number of the block being
interpreted.
-' -- addr false "dash-tick"
-- true
Used in the form:
-' <name>
Leave the parameter field of <name> beneath zero (false) if
<name> can be found in the search order; leave only true if
not found.
-MATCH addr1 +n1 addr2 +n2 -- addr3 flag "dash-match"
Attempt to find the +n2-length text string beginning at
addr2 somewhere in the +n1-length text string beginning at
addr1. Return the last+1 address addr3 of the match point
and a flag which is zero if a match exists.
-TEXT addr1 +n1 addr2 -- n2 "dash-text"
Compare two strings over the length +n1 beginning at addr1
and addr2. Return zero if the strings are equal. If
unequal, return n2, the difference between the last
characters compared: addr1(i) - addr2(i).
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B. UNCONTROLLED REFERENCE WORDS
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/LOOP +n -- C,I "up-loop"
sys -- (compiling)
A do-loop terminating word. The loop index is incremented
by the positive value +n. If the unsigned magnitude of the
resultant index is greater than the limit, then the loop is
terminated, otherwise execution returns to the corresponding
DO . The comparison is unsigned magnitude. sys is balanced
with its corresponding DO . See: DO
1+! addr -- "one-plus-store"
Add one to the 16-bit contents at addr.
1-! addr -- "one-minus-store"
Subtract one from the 16-bit contents at addr.
;: -- addr C,I"semi-colon-colon"
Used to specify a new defining word:
: <namex> <name>
When <namex> is executed, it creates an entry for the new
word <name>. Later execution of <name> will execute the
sequence of words between ;: and ; , with the address of the
first (if any) parameters associated with <name> on the
stack.
;S -- Interpret only"semi-s"
Stop interpretation of a block.
<> w1 w2 -- flag "not-equal"
flag is true if w1 is not equal to w2.
<BUILDS -- "builds"
Used in conjunction with DOES> in defining words, in the
form:
: <namex> ... <BUILDS ... DOES> ... ;
and then:
<namex> <name>
When <namex> executes, <BUILDS creates a dictionary entry
for the new <name>. The sequence of words between <BUILDS
and DOES> established a parameter field for <name>. When
<name> is later executed, the sequence of words following
DOES> will be executed, with the parameter field address of
<name> on the data stack.
<CMOVE addr1 addr2 u -- "reverse-c-move"
A synonym for CMOVE> .
>< 16b1 -- 16b2 "byte-swap"
Swap the high and low bytes within 16b1.
>MOVE< addr1 addr2 u -- "byte-swap-move"
Move u bytes beginning at addr1 to the memory beginning at
addr2. During this move, the order of each byte pair is
reversed.
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B. UNCONTROLLED REFERENCE WORDS
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@BITS addr 16b1 -- 16b2 "fetch-bits"
Return the 16-bits at addr masked by 16b1.
AGAIN -- C,I
sys -- (compiling)
Effect an unconditional jump back to the start of a BEGIN-
AGAIN loop. sys is balanced with its corresponding BEGIN .
See: BEGIN
ASCII -- char I,M "as-key"
-- (compiling)
Used in the form:
ASCII ccc
where the delimiter of ccc is a space. char is the ASCII
character value of the first character in ccc. If
interpreting, char is left on the stack. If compiling,
compile char as a literal so that when the colon definition
is later executed, char is left on the stack.
ASHIFT 16b1 n -- 16b2 "a-shift"
Shift the value 16b1 arithmetically n bits left if n is
positive, shifting zeros into the least significant bit
positions. If n is negative, 16b1 is shifted right; the
sign is included in the shift and remains unchanged.
B/BUF -- 1024 "bytes-per-buffer"
A constant leaving 1024, the number of bytes per block
buffer.
BELL --
Activate a terminal bell or noise-maker as appropriate to
the device in use.
CHAIN -- M
Used in the form:
CHAIN <name>
Connect the CURRENT vocabulary to all definitions that might
be entered into the vocabulary <name> in the future. The
CURRENT vocabulary may not be FORTH or ASSEMBLER . Any
given vocabulary may only be chained once, but may be the
object of any number of chainings. For example, every user-
defined vocabulary may include the sequence:
CHAIN FORTH
CONTINUED u -- M
Continue interpretation at block u.
CUR -- addr
A variable pointing to the physical record number before
which the tape is currently positioned. REWIND sets CUR=1.
DBLOCK ud -- addr M "d-block"
Identical to BLOCK but with a 32-bit block unsigned number.
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B. UNCONTROLLED REFERENCE WORDS
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DPL -- addr U "d-p-l"
A variable containing the number of places after the
fractional point for input conversion.
FLD -- addr U "f-l-d"
A variable pointing to the field length reserved for a
number during output conversion.
H. u -- M "h-dot"
Output u as a hexadecimal integer with one trailing blank.
The current base is unchanged.
I' -- w C "i-prime"
Used within a colon definition executed only from within a
do-loop to return the corresponding loop index.
IFEND Interpret only"if-end"
Terminate a conditional interpretation sequence begun by
IFTRUE .
IFTRUE flag -- Interpret only "if-true"
Begin an:
IFTRUE ... OTHERWISE ... IFEND
conditional sequence. These conditional words operated
like:
IF ... ELSE ... THEN
except that they cannot be nested, and are to be used only
during interpretation. In conjunction with the words [ and
] the words [ and ] they may be used within a colon
definition to control compilation, although they are not to
be compiled.
INDEX u1 u2 -- M
Print the first line of each screen over the range {u1..u2}.
This displays the first line of each screen of source text,
which conventionally contains a title.
LAST -- addr U
A variable containing the address of the beginning of the
last dictionary entry made, which may not yet be a complete
or valid entry.
LINE +n -- addr M
addr is the address of the beginning of line +n for the
screen whose number is contained in SCR . The range of +n
is {0..15}.
LINELOAD +n u -- "line-load"
Begin interpretation at line +n of screen u.
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B. UNCONTROLLED REFERENCE WORDS
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LOADS u -- M
A defining word executed in the form:
u LOADS <name>
When <name> is subsequently executed, block u will be
loaded.
MAP0 -- addr "map-zero"
A variable pointing to the first location in the tape map.
MASK n -- 16b
16b is a mask of n most-significant bits if n is positive,
or n least-significant bits if n is negative.
MOVE addr1 addr2 u --
The u bytes at address addr1 are moved to address addr2.
The data are moved such that the u bytes remaining at
address addr2 are the same data as was originally at address
addr1. If u is zero nothing is moved.
MS +n -- M "m-s"
Delay for approximately +n milliseconds.
NAND 16b1 16b2 -- 16b3
16b3 is the one's complement of the logical AND of 16b1 with
16b2.
NOR 16b1 16b2 -- 16b3
16b3 is the one's complement of the logical OR of 16b1 with
16b2.
NUMBER addr -- d
Convert the count and character string at addr, to a signed
32-bit integer, using the value of BASE . If numeric
conversion is not possible, an error condition exists. The
string may contain a preceding minus sign.
O. u -- M "o-dot"
Print u in octal format with one trailing blank. The value
in BASE is unaffected.
OTHERWISE -- Interpret only
An interpreter-level conditional word. See: IFTRUE
PAGE -- M
Clear the terminal screen or perform a form-feed action
suitable to the output device currently active.
READ-MAP -- M "read-map"
Read to the next file mark on tape constructing a
correspondence table in memory (the map) relating physical
block position to logical block number. The tape should
normally be rewound to its load point before executing READ-
MAP .
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REMEMBER -- M
A defining word executed in the form:
REMEMBER <name>
Defines a word which, when executed, will cause <name> and
all subsequently defined words to be deleted from the
dictionary. <name> may be compiled into and executed from a
colon definition. The sequence
DISCARD REMEMBER DISCARD
provides a standardized preface to any group of transient
word definitions.
REWIND -- M
Rewind the tape to its load point, setting CUR equal to one.
ROTATE 16b1 n -- 16b2
Rotate 16b1 left n bits if n is positive, right n bits if n
is negative. Bits shifted out of one end of the cell are
shifted back in at the opposite end.
S0 -- addr U "s-zero"
A variable containing the address of the bottom of the
stack.
SET 16b addr -- M
A defining word executed in the form:
16b addr SET <name>
Defines a word <name> which, when executed, will cause the
value 16b to be stored at addr.
SHIFT 16b1 n -- 16b2
Logical shift 16b1 left n bits if n is positive, right n
bits if n is negative. Zeros are shifted into vacated bit
positions.
TEXT char -- M
Accept characters from the input stream, as for WORD , into
PAD , blank-filling the remainder of PAD to 84 characters.
USER +n -- M
A defining word executed in the form:
+n USER <name>
which creates a user variable <name>. +n is the offset
within the user area where the value for <name> is stored.
Execution of <name> leaves its absolute user area storage
address.
WORDS -- M
List the word names in the first vocabulary of the currently
active search order.
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\LOOP +n -- C,I "down-loop"
sys -- (compiling)
A do-loop terminating word. The loop index is decremented
by the positive value +n. If the unsigned magnitude of the
resultant index is less than or equal to the limit, then the
loop is terminated, otherwise execution returns to the
corresponding DO . The comparison is unsigned. sys is
balanced with its corresponding DO . See: DO
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