• ← ReleaseHold
• → Unevaluated

Sequence

WMA link

Sequence[$x_1$, $x_2$, ...]

represents a sequence of arguments to a function.

Sequence is automatically spliced in, except when a function has attribute SequenceHold
(like assignment functions).

• • f[x, Sequence[a, b], y]

• • Attributes[Set]

• • a = Sequence[b, c];

• • a

Apply Sequence to a list to splice in arguments:

• • list = {1, 2, 3};

• • f[Sequence @@ list]

Inside Hold or a function with a held argument, Sequence is
spliced in at the first level of the argument:

• • Hold[a, Sequence[b, c], d]

If Sequence appears at a deeper level, it is left unevaluated:

• • Hold[{a, Sequence[b, c], d}]