VBScript Search for Repeated Words

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You can use this recipe to find words that appear more than once on a line, such as the the.

[edit] code

Dim fso,s,re,line,lineNbr
Set fso = CreateObject("Scripting.FileSystemObject")
Set s = fso.OpenTextFile(WScript.Arguments.Item(0), 1, True)
Set re = New RegExp
re.Pattern = "\b(\w+)\s\1\b"
lineNbr = 0
Do While Not s.AtEndOfStream
    line = s.ReadLine()
    lineNbr = lineNbr + 1
    If re.Test(line) Then
        WScript.Echo "Found match: '" & line & "' at line " & lineNbr
    End If
Loop
s.Close

[edit] How It Works

The most important aspect of this regular expression is the back reference, which is \1 in all the previous recipes. The back reference is just a way of saying “whatever you found in the first group.” The parentheses in the expression define the group. Here’s a breakdown of the expression:

Regular Expression Description
\b is a word boundary, followed by . . .
(...) a group (explained next), then . . .
\s a space . . .
+ one or more times, then . . .
\1 whatever was found in the group, and lastly . . .
\b a word boundary.
The group is simply (\w+), which is as follows:
\w a word character . . .
+ found one or more times.

This will match a word. The expression begins and ends with a word boundary anchor. This is to prevent the expression from matching a string such as quarterback backrub. If the word boundary anchors are removed, the expression will start matching subsections of words.

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