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:
string+ false?
ensure-string
string-delimit
Version: 3.99.0.23

 

3 String utilities

 (require (planet untyped/unlib/string))

Useful string utilities. Compatible with PLT 4 languages.

(string+false? item)  boolean?

  item : any

Returns #t if item is a string and #f otherwise.

(ensure-string item)  any

  item : any

Converts bytes arguments to strings: passes all other arguments straight through.

(string-delimit

 

items

 

 

 

 

 

 

delimiter

 

 

 

 

 

 [

#:prefix prefix

 

 

 

 

 

 

#:suffix suffix])

 

 

string?

  items : (listof string?)

  delimiter : string?

  prefix : (U string? #f) = #f

  suffix : (U string? #f) = #f

Similar to string-join from SRFI 13, except that the optional #:prefix and #:suffix arguments can be provided to add a prefix or suffix string.

Examples:

  > (string-delimit '("1" "2" "3") ",")

  "1,2,3"

  > (string-delimit '("1" "2" "3") "," #:prefix "[")

  "[1,2,3"

  > (string-delimit '("1" "2" "3") "," #:suffix "]")

  "1,2,3]"

  > (string-delimit '("1" "2" "3") "," #:prefix "[" #:suffix "]")

  "[1,2,3]"

  > (string-delimit '("1" "2" "3") "," #:prefix #f #:suffix #f)

  "1,2,3"