▼ |  | Mz Lib: Legacy Libraries

1 | mzlib/ a-signature
2 | mzlib/ a-unit
3 | mzlib/ async-channel
4 | mzlib/ awk
5 | mzlib/ class
6 | mzlib/ class100
7 | mzlib/ cm
8 | mzlib/ cm-accomplice
9 | mzlib/ cmdline
10 | mzlib/ cml
11 | mzlib/ compat
12 | mzlib/ compile
13 | mzlib/ contract
14 | mzlib/ control
15 | mzlib/ date
16 | mzlib/ deflate
17 | mzlib/ defmacro
18 | mzlib/ etc
19 | mzlib/ file
20 | mzlib/ for
21 | mzlib/ foreign
22 | mzlib/ include
23 | mzlib/ inflate
24 | mzlib/ integer-set
25 | mzlib/ kw
26 | mzlib/ list
27 | mzlib/ match
28 | mzlib/ math
29 | mzlib/ md5
30 | mzlib/ os
31 | mzlib/ pconvert
32 | mzlib/ pconvert-prop
33 | mzlib/ plt-match
34 | mzlib/ port
35 | mzlib/ pregexp
36 | mzlib/ pretty
37 | mzlib/ process
38 | mzlib/ restart
39 | mzlib/ runtime-path
40 | mzlib/ sandbox
41 | mzlib/ sendevent
42 | mzlib/ serialize
43 | mzlib/ shared
44 | mzlib/ string
45 | mzlib/ struct
46 | mzlib/ stxparam
47 | mzlib/ surrogate
48 | mzlib/ tar
49 | mzlib/ thread
50 | mzlib/ trace
51 | mzlib/ traceld
52 | mzlib/ trait
53 | mzlib/ transcr
54 | mzlib/ unit
55 | mzlib/ unit-exptime
56 | mzlib/ unit200
57 | mzlib/ unitsig200
58 | mzlib/ zip
| Bibliography
| Index

On this page:

=?
<?
>?
<=?
>=?
1+
1-
gentmp
flush-output-port
real-time
atom?
define-structure
getprop
putprop
new-cafe

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(require mzlib/compat)

The mzlib/compat library defines a number of procedures and syntactic forms that are commonly provided by other Scheme implementations. Most of the procedures are aliases for mzscheme procedures.

> procedure (=? n ...+) → boolean?
> n : number?
> procedure (<? n ...+) → boolean?
> n : real?
> procedure (>? n ...+) → boolean?
> n : real?
> procedure (<=? n ...+) → boolean?
> n : real?
> procedure (>=? n ...+) → boolean?
> n : real?

Same as =, <, etc.

> procedure (1+ n) → number?
> n : number?
> procedure (1- n) → number?
> n : number?

Same as add1 and sub1.

> procedure (gentmp [base]) → symbol?
> base : (or/c string? symbol?) = "g"

Same as gensym.

> procedure (flush-output-port [o]) → void?
> o : output-port? = (current-output-port)

Same as flush-output.

> procedure (real-time) → exact-integer?

Same as current-milliseconds.

> procedure (atom? v) → any
> v : any/c

Same as (not (pair? v)) (which does not actually imply an atomic value).

> syntax (define-structure (name-id field-id ...))
> (define-structure (name-id field-id ...)
> ((init-field-id init-expr) ...))

Like define-struct, except that the name-id is moved inside the parenthesis for fields. In addition, init-field-ids can be specified with automatic initial-value expression.

The init-field-ids do not have corresponding arguments for the make-name-id constructor. Instead, each init-field-id’s init-expr is evaluated to obtain the field’s value when the constructor is called. The field-ids are bound in init-exprs, but not other init-field-ids.

Examples:
> > (define-structure (add left right) ([sum (+ left right)]))
> > (add-sum (make-add 3 6))
> 9

> procedure (getprop sym property [default]) → any/c
> sym : symbol?
> property : symbol?
> default : any/c = #f
> procedure (putprop sym property value) → void?
> sym : symbol?
> property : symbol?
> value : any/c

The getprop function gets a property value associated with sym. The property argument names the property to be found. If the property is not found, default is returned.

The properties obtained with getprop are the ones installed with putprop.

> procedure (new-cafe [eval-handler]) → any
> eval-handler : (any/c . -> . any) = #f

Emulates Chez Scheme’s new-cafe by installing eval-handler into the current-eval parameter while running read-eval-print. In addition, current-exit is set to escape from the call to new-cafe.
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