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how to replace text in files

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Tudor Girba-2

how to replace text in files

Hi,

How would you replace a piece of text in a file with another one and persist the change on disk?

Right now, I have:

file := 'path' asFileReference

contents := file readStreamDo: #contents.

newContents := contents copyReplaceAll: 'PATTERN' with: 'TARGET'.

file

ensureDelete;

writeStreamDo: [ :s | s nextPutAll: newContents asString ]

Any idea to make this more concise?

Cheers,

Doru

www.tudorgirba.com

"Every thing has its own flow"

Peter Uhnak

Re: how to replace text in files

On Fri, Jun 26, 2015 at 10:56 AM, Tudor Girba <[hidden email]> wrote:

Hi,

How would you replace a piece of text in a file with another one and persist the change on disk?

Right now, I have:

file := 'path' asFileReference
contents := file readStreamDo: #contents.
newContents := contents copyReplaceAll: 'PATTERN' with: 'TARGET'.

why not just

newContents := file contents copyReplaceAll: ...

and since we already have contents

why not also add

~~~~~~~~~~~~~~~~

AbstractFileReference>>contents: aCollection

self writeStreamDo: [ :stream |

stream

resetContents;

nextPutAll: aCollection

]

~~~~~~~~~~~~~~~~

And then you could do

~~~~~~~~~~~~~~~~~~~~~~~

file := 'path' asFileReference

newContents := file contents copyReplaceAll: 'PATTERN' with: 'TARGET'.

file

ensureDelete;

contents: newContents

~~~~~~~~~~~~~~~~~~~~~~~

However personally I really don't like the "ensureDelete" (or FileStream forceNewFileNamed: aFileName do: [ :stream | ... ],

and I got burned by it couple of times when I forgot about it... easy way to corrupt your files.

I mean, what is the use-case of overriding just the beginning? In most languages the default is write (override whole file) and append (add at the end)... and if you need fine control then you fseek().

This is maybe so each write to the stream doesn't reset it? What about clearing just on the first write to the stream?

Peter