_exprseq
-- expression
sequencesThe function call _exprseq(
object1,
object2...)
is the internal representation of the
expression sequence object1, object2...
.
object1, object2, ...
_exprseq(object1,
object2...)
object1, object2, ... |
- | arbitrary MuPAD objects |
an expression of type "_exprseq"
or the void object of
type DOM_NULL
.
_exprseq(
object1, object2,
...)
. On the screen, sequences are printed as
object1, object2, ...
._exprseq(
)
and the equivalent call
null()
yield the void
object of type DOM_NULL
.DOM_NULL
are removed
from it, automatically.$
operator is a
useful tool for generating sequences._exprseq
is a function of the system kernel.A sequence is generated by ``concatenating'' objects
with commas. The resulting object is of type
"_exprseq"
:
>> a, b, sin(x)
a, b, sin(x)
>> op(%, 0), type(%)
_exprseq, "_exprseq"
On the screen, _exprseq
just returns its
argument sequence:
>> _exprseq(1, 2, x^2 + 5) = (1, 2, x^2 + 5)
2 2 (1, 2, x + 5) = (1, 2, x + 5)
The object of domain DOM_NULL
(the ``empty
sequence'') is automatically removed from expression sequences:
>> 1, 2, null(), 3
1, 2, 3
Expression sequences are flattened. The following sequence does not have 2 operands, where the second operand is a sequence. Instead, it is flattened to a sequence with 3 operands:
>> x := 1: y := 2, 3: x, y
1, 2, 3
>> delete x, y:
Sequences are used to build sets and lists. Sequences can also be passed to functions that accept several arguments:
>> s := 1, 2, 3: {s}, [s], f(s)
{1, 2, 3}, [1, 2, 3], f(1, 2, 3)
>> delete s: