1 Exception utilities
2 Number utilities
3 String utilities
4 Bytes utilities
5 Symbol utilities
6 List utilities
7 PLT 4x hash utilities
8 PLT 3x hash utilities
9 URL utilities
10 Contract utilities
11 File and path utilities
12 Parameter utilities
13 Syntax utilities
14 SRFI19 time utilities
15 Scribble utilities
16 Generators
17 Generators (short names)
18 Pipelines
19 Write-through cache
20 Yieldable procedures
21 Debugging tools
22 Profiling tools
23 Logging tools
On this page:
number+ false?
integer+ false?
natural?
natural+ false?
number+ false->symbol+ false
symbol+ false->number+ false
number+ false->string+ false
string+ false->number+ false
Version: 4.0.1.2

 

2 Number utilities

 (require (planet untyped/unlib/number))

Useful number utilities.

(number+false? item)  boolean?

  item : any

Returns #t if item is a number or #scheme[#f].

(integer+false? item)  boolean?

  item : any

Returns #t if item is an integer or #scheme[#f].

(natural? item)  boolean?

  item : any

Returns #t if item is an natural number (>= 0).

(natural+false? item)  boolean?

  item : any

Returns #t if item is an natural number (>= 0) or #f.

(number+false->symbol+false num)  (U symbol? #f)

  num : (U number? #f)

A version of number->symbol that accepts and passes through #f.

(symbol+false->number+false sym)  (U number? #f)

  sym : (U symbol? #f)

A version of symbol->number that accepts and passes through #f.

(number+false->string+false num)  (U string? #f)

  num : (U number? #f)

A version of number->string that accepts and passes through #f.

(string+false->number+false str)  (U number? #f)

  str : (U string? #f)

A version of string->number that accepts and passes through #f.