▼ |  | Unstable: May Change Without Warning

1 | Guidelines for Developing unstable Libraries
2 | Automata: Compiling State Machines
3 | Bytes
4 | Contracts
5 | Contracts for Macro Subexpressions
6 | Debugging
7 | Definitions
8 | Errors
9 | Futures
10 | Functions
11 | Hash Tables
12 | Interface-Oriented Programming for Classes
13 | Lazy Require
14 | Lists
15 | Logging
16 | Macro Testing
17 | Mark Parameters
18 | Match
19 | Open place expressions
20 | Options
21 | Parameter Groups
22 | Pretty-Printing
23 | Re-Contracting Identifiers
24 | Sandbox
25 | Sequences
26 | Strings
27 | Structs
28 | Struct Printing
29 | Syntax
30 | Temporal Contracts: Explicit Contract Monitors
31 | Unix Domain Sockets
32 | 2D Syntax

On this page:

in-syntax
in-pairs
in-sequence-forever
sequence-lift
in-slice

5.92
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### 25`` Sequences

Sam Tobin-Hochstadt <samth@ccs.neu.edu>

This library is unstable; compatibility will not be maintained. See Unstable: May Change Without Warning for more information.

(require unstable/sequence) | package: base

> procedure (in-syntax stx) → sequence?
> stx : syntax?

Produces a sequence equivalent to (syntax->list lst).
An in-syntax application can provide better performance for syntax iteration when it appears directly in a for clause.

Example:
> > (for/list ([x (in-syntax #'(1 2 3))])
> x)
> '(#<syntax:2:0 1> #<syntax:2:0 2> #<syntax:2:0 3>)

> procedure (in-pairs seq) → sequence?
> seq : sequence?

Produces a sequence equivalent to (in-parallel (sequence-lift car seq) (sequence-lift cdr seq)).

> procedure (in-sequence-forever seq val) → sequence?
> seq : sequence?
> val : any/c

Produces a sequence whose values are the elements of seq, followed by val repeated.

> procedure (sequence-lift f seq) → sequence?
> f : procedure?
> seq : sequence?

Produces the sequence of f applied to each element of seq.

Example:
> > (for/list ([x (sequence-lift add1 (in-range 10))])
> x)
> '(1 2 3 4 5 6 7 8 9 10)

> > > The subsequent bindings were added by David Vanderson.

> procedure (in-slice length seq) → sequence?
> length : exact-positive-integer?
> seq : sequence?

Returns a sequence where each element is a list with length elements from the given sequence.

Example:
> > (for/list ([e (in-slice 3 (in-range 8))]) e)
> '((0 1 2) (3 4 5) (6 7))

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