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Returns the current time.
now: () -> num
Returns the lapsed time in seconds since this qulog process was started
exec_time: () -> num
Returns the time at which this qulog process was started
start_time: () -> num
Returns a random number in [0,1)
.
random_num: () -> num
Returns a random number in the interval [Lower, Upper]
.
random_int: (int, int) -> num
Returns the union of sets S1
and S2
.
union: ({T}, {T}) -> {T}
Returns the intersection of sets S1
and S2
.
inter: ({T}, {T}) -> {T}
Returns the set difference of sets S1
and S2
.
diff: ({T}, {T}) -> {T}
Returns the concatination of lists L1
and L2
.
<> : ([T], [T]) -> [T]
Returns the concatination of strings S1
and S2
.
++ : (string, string) -> string
Returns the length of the list, set, or string L
.
# : [T] -> nat | {T} -> nat | string -> nat
Returns the compound term obtained by applying F
to Args
.
@.. : (term, [term]) -> term
Example:
| ?? @..(a, [1,2]). a(1, 2) : term
@..
can also be used to split up a compound term as in the following example.
| ?? a(1,2) =? F@..Args. F = a : atom Args = [1, 2] : [nat]
Here Name
is an atom that must have been initialised with a statement
int Name:=Integer
, e.g. int count:=0
or
num Name:=Number
, e.g. num savings:=678.50
in the program. It returns the current value associated with Name
which can be updated by primitive actions (see :=).
Next: Other Relations, Previous: Arithmetic, Up: Built-Ins [Contents][Index]