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String.collect Function (F#)

Builds a new string whose characters are the results of applying a specified function to each of the characters of the input string and concatenating the resulting strings.

Namespace/Module Path: Microsoft.FSharp.Core.String

Assembly: FSharp.Core (in FSharp.Core.dll)

// Signature:
String.collect : (char -> string) -> string -> string

// Usage:
String.collect mapping str

Parameters

  • mapping
    Type: char -> string

    The function to produce a string from each character of the input string.

  • str
    Type: string

    The input string.

Exceptions

Exception

Condition

ArgumentNullException

Thrown when the input string is null.

Return Value

The concatenated string.

Remarks

This function is named Collect in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.

Example

The following code shows how to use String.collect.

let spaceOut inputString =
     String.collect (fun c -> sprintf "%c " c) inputString
printfn "%s" (spaceOut "Hello World!")

Output

H e l l o   W o r l d ! 

Platforms

Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

Version Information

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

See Also

Reference

Core.String Module (F#)

Microsoft.FSharp.Core Namespace (F#)