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 Contract utilities
10 File and path utilities
11 Parameter utilities
12 Syntax utilities
13 SRFI19 time utilities
14 Generators
15 Generators (short names)
16 Pipelines
17 Write-through cache
18 Yieldable procedures
19 Debugging tools
20 Profiling tools
21 Logging tools
On this page:
number+ false?
integer+ false?
natural?
natural+ false?
Version: 3.99.0.23

 

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.