+Idx
- Prefix class for maintaining non-unique full-text indexes to
+String relations, a subclass of +Ref. Accepts optional arguments for the
minimally indexed substring length (defaults to 3), and a +Hook attribute. Often used in combination
with the +Sn soundex index, or the
+Fold index prefix classes. See also
Database.
(rel nm (+Sn +Idx +String)) # Name
+IdxFold
- Prefix class for maintaining non-unique indexes to subsequent substrings of
the
folded individual words of
+String relations. Accepts optional
arguments for the minimally indexed substring length (defaults to 3), and a
+Hook attribute. See also +Idx and Database.
(rel nm (+IdxFold +String)) # Item Description
+index
- Abstract base class of all database B-Tree index relations (prefix classes
for
+relations). The class
hierarchy includes +Key, +Ref, +Idx and +IdxFold. See also Database.
(isa '+index Rel) # Check for an index relation
(id 'num ['num]) -> sym
(id 'sym [NIL]) -> num
(id 'sym T) -> (num . num)
- Converts one (the internal block number) or two (file and block) numbers to
an external symbol, or an external symbol to a number or a pair of numbers.
: (id 7)
-> {7}
: (id 1 2)
-> {2}
: (id '{A2})
-> 2
: (id '{A2} T)
-> (2 . 2)
(idx 'var 'any 'flg) -> lst
(idx 'var 'any) -> lst
(idx 'var) -> lst
- Maintains an index tree in
var, and checks for the existence of
any. If any is contained in var, the
corresponding subtree is returned, otherwise NIL. In the first
form, any is destructively inserted into the tree if
flg is non-NIL (and any was not already
there), or deleted from the tree if flg is NIL. If all
elements are inserted in sorted order, the tree degenerates into a linear list.
In such cases, 0 may be passed for flg to randomize
the insertion order. The second form only checks for existence, but does not
change the index tree. In the third form (when called with a single
var argument) the contents of the tree are returned as a sorted
list.
See also lup, enum, hash, rev, depth, sort, balance and member.
: (idx 'X 'd T) # Insert data
-> NIL
: (idx 'X 2 T)
-> NIL
: (idx 'X '(a b c) T)
-> NIL
: (idx 'X 17 T)
-> NIL
: (idx 'X 'A T)
-> NIL
: (idx 'X 'd T)
-> (d (2 NIL 17 NIL A) (a b c)) # 'd' already existed
: (idx 'X T T)
-> NIL
: X # View the index tree
-> (d (2 NIL 17 NIL A) (a b c) NIL T)
: (idx 'X 'A) # Check for 'A'
-> (A)
: (idx 'X 'B) # Check for 'B'
-> NIL
: (idx 'X)
-> (2 17 A d (a b c) T) # Get list
: (idx 'X 17 NIL) # Delete '17'
-> (17 NIL A)
: X
-> (d (2 NIL A) (a b c) NIL T) # View it again
: (idx 'X)
-> (2 A d (a b c) T) # '17' is deleted
: (off X Y)
-> NIL
: (for I 9 (idx 'X I T)) # Sorted insert order
-> NIL
: (for I 9 (idx 'Y I 0)) # Randomize
-> NIL
: (view X T)
9
8
7
6
5
4
3
2
1
-> NIL
: (view Y T)
9
8
7
6
5
4
3
2
1
-> NIL
(if 'any1 any2 . prg) -> any
- Conditional execution: If the condition
any1 evaluates to
non-NIL, any2 is evaluated and returned. Otherwise,
prg is executed and the result returned. See also ifn, cond, when and if2.
: (if (> 4 3) (println 'OK) (println 'Bad))
OK
-> OK
: (if (> 3 4) (println 'OK) (println 'Bad))
Bad
-> Bad
(if2 'any1 'any2 any3 any4 any5 . prg) -> any
- Four-way conditional execution for two conditions: If both conditions
any1 and any2 evaluate to non-NIL,
any3 is evaluated and returned. Otherwise, any4 or
any5 is evaluated and returned if any1 or
any2 evaluate to non-NIL, respectively. If none of the
conditions evaluate to non-NIL, prg is executed and
the result returned. See also if and
cond.
: (if2 T T 'both 'first 'second 'none)
-> both
: (if2 T NIL 'both 'first 'second 'none)
-> first
: (if2 NIL T 'both 'first 'second 'none)
-> second
: (if2 NIL NIL 'both 'first 'second 'none)
-> none
(ifn 'any1 any2 . prg) -> any
- Conditional execution ("If not"): If the condition
any1
evaluates to NIL, any2 is evaluated and returned.
Otherwise, prg is executed and the result returned. See also
if, nor, nand, unless and nond.
: (ifn (= 3 4) (println 'OK) (println 'Bad))
OK
-> OK
(import . lst) -> lst
- Wrapper function for
intern.
Typically used to import symbols from other namespaces, as created by symbols. lst should be a list
of symbols. See also pico,
private and
local and
export.
: (import libA~foo libB~bar)
-> (foo bar)
(in 'any . prg) -> any
- Opens
any as input channel during the execution of
prg. The current input channel will be saved and restored
appropriately. If the argument is NIL, standard input is used. If
the argument is a symbol, it is used as a file name (opened in read-only mode).
If it is a positive number, it is used as the descriptor of an open file. If it
is a negative number, the saved input channel such many levels above the current
one is used. Otherwise (if it is a list), it is taken as a command with
arguments, and a pipe is opened for input. The (system dependent) exit status
code of the child process is stored in the global variable @@. See also out, err, fd, ipid, call, load, file, poll, pipe and ctl.
: (in "a" (list (read) (read) (read))) # Read three items from file "a"
-> (123 (a b c) def)
: (in '(file "-b" "--mime" "bin/picolisp") # Get the mime type
(line T) )
-> "application/x-executable; charset=binary"
(inc 'num) -> num
(inc 'var ['num]) -> num
- The first form returns the value of
num incremented by 1. The
second form increments the VAL of var by 1, or by
num. If the first argument is NIL, it is returned
immediately. (inc Num) is equivalent to (+ Num 1) and
(inc 'Var) is equivalent to (set 'Var (+ Var 1)). See
also dec and +.
: (inc 7)
-> 8
: (inc -1)
-> 0
: (zero N)
-> 0
: (inc 'N)
-> 1
: (inc 'N 7)
-> 8
: N
-> 8
: (setq L (1 2 3 4))
-> (1 2 3 4)
: (inc (cdr L))
-> 3
: L
-> (1 3 3 4)
(inc! 'obj 'sym ['num]) -> num
- Transaction wrapper function for
inc. num defaults to 1. Note that
for incrementing a property value of an entity typically the inc!> message is used. See also
new!, request!, set! and put!.
(inc! Obj 'cnt 0) # Incrementing a property of a non-entity object
(index 'any 'lst) -> cnt | NIL
- Returns the
cnt position of any in
lst, or NIL if it is not found. See also offset and sub?.
: (index 'c '(a b c d e f))
-> 3
: (index '(5 6) '((1 2) (3 4) (5 6) (7 8)))
-> 3
(info 'any ['flg]) -> (cnt|flg dat . tim)
- Returns information about a file with the name
any: The current
size cnt in bytes, and the modification date and time (UTC, or
local time if flg is zero). For directories, T is
returned instead of the size, and NIL for other non-regular files.
The file argument itself is stored in the global variable @@). If flg is non-NIL
and any is the name of a symbolic link, then the link itself is
used, not the file that it refers to. See also dir, date and time.
$ ls -l x.l
-rw-r--r-- 1 abu users 208 Jun 17 08:58 x.l
$ pil +
: (info "x.l")
-> (208 730594 . 32315)
: (stamp 730594 32315)
-> "2000-06-17 08:58:35"
(init 'tree ['any1] ['any2]) -> lst
- Initializes a structure for stepping iteratively through a database tree.
any1 and any2 may specify a range of keys. If
any2 is greater than any1, the traversal will be in
opposite direction. See also tree,
step, iter and scan.
: (init (tree 'nr '+Item) 3 5)
-> (((3 . 5) ((3 NIL . {B3}) (4 NIL . {B4}) (5 NIL . {B5}) (6 NIL . {B6}))))
(input exe . prg) -> any
- Establishes an input stream, by redirecting the current input channel during
the execution of
prg. The current input channel will be saved and
restored appropriately. exe is executed (in the context of the
original input channel) whenever a character is required by read calls in
prg, and should return a single character upon each execution. See
also output, in and pipe.
: (input "A" (char))
-> "A"
: (let L (chop "(+ 2 (* 3 4))")
(input (++ L) (read)) )
-> (+ 2 (* 3 4))
: (let L (chop "AQIDBAUGBw==")
(input (++ L)
(while (ext:Base64)
(printsp @) ) ) )
1 2 3 4 5 6 7 -> 7
(insert 'cnt 'lst 'any) -> lst
- Inserts
any into lst at position cnt.
This is a non-destructive operation. See also remove, place, append, delete and replace.
: (insert 3 '(a b c d e) 777)
-> (a b 777 c d e)
: (insert 1 '(a b c d e) 777)
-> (777 a b c d e)
: (insert 9 '(a b c d e) 777)
-> (a b c d e 777)
(intern 'any ['nsp]) -> sym
- Creates or finds an internal symbol. If a symbol with the name
any is already intern, it is returned. Otherwise, any
is interned in the current namespace and returned. If nsp is
non-NIL, any is always interned in the current
namespace (if nsp is T) or in the given namespace,
even if it is found in other namespaces. See also symbols, zap, import and extern.
: (intern "abc")
-> abc
: (intern 'car)
-> car
: ((intern "car") (1 2 3))
-> 1
: ((intern '("c" "a" "r")) (1 2 3))
-> 1
(ipid) -> pid | NIL
- Returns the corresponding process ID when the current input channel is
reading from a pipe, otherwise
NIL. See also opid, in, pipe and load.
: (in '(ls "-l") (println (line T)) (kill (ipid)))
"total 7364"
-> T
(isa 'cls|typ 'obj) -> obj | NIL
- Returns
obj when it is an object that inherits from
cls or type. See also OO
Concepts, class, type, new and object.
: (isa '+Address Obj)
-> {A17}
: (isa '(+Male +Person) Obj)
-> NIL
isa/2
- Pilog predicate that succeeds if the second
argument is of the type or class given by the first argument, according to the
isa function. Typically used in
db/3 or select/3 database queries. See also
same/3, bool/3, range/3, head/3, fold/3, part/3 and tolr/3.
: (? (db nm +Person @Prs) (isa +Woman @Prs) (val @Nm @Prs nm))
@Prs={A44} @Nm="Alexandra of Denmark"
@Prs={A124} @Nm="Alice Maud Mary"
@Prs={A21} @Nm="Anne"
@Prs={A57} @Nm="Augusta Victoria". # Stop
(iter 'tree ['fun] ['any1] ['any2] ['flg])
- Iterates through a database tree by applying
fun to all values.
fun defaults to println. any1 and
any2 may specify a range of keys. If any2 is greater
than any1, the traversal will be in opposite direction. Note that
the keys need not to be atomic, depending on the application's index structure.
If flg is non-NIL, partial keys are skipped. See also
tree, ubIter, scan, init and step.
: (iter (tree 'nr '+Item))
{B1}
{B2}
{B3}
{B4}
{B5}
{B6}
-> NIL
: (iter (tree 'nr '+Item) '((This) (println (: nm))))
"Main Part"
"Spare Part"
"Auxiliary Construction"
"Enhancement Additive"
"Metal Fittings"
"Gadget Appliance"
"Testartikel"
-> NIL