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From: Stéphane Ducasse <stephane.ducasse@inria.fr> Date: February 20, 2011 8:54:54 AM GMT+01:00 To: Colin Putney <colin@wiresong.com> Subject: Re: Need your point of view on FSPath * and others

Thanks I will take into that and write better comments.

I was looking at makeRelative: they look to me as 'private methods' used for double dispatch while relativeTo: is the public one. I imagine that I'm correct.

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With that in mind, I added the #/ and #* methods to make the filesystem API easier to use. I think binary selectors are under-exploited in Smalltalk, and we'd gain a lot in terms of succinct and readable code by making better use of them.

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2- Then I was wondering if it would not be good to have validating creation methods

(FSPath * 'parent/child/') isRelative true (FSPath * '/parent/child/') isAbsolute false because the string is not checked FSPath * '/parejhkjhhg %% ^%$%^(%$546547675 nt??child/'

That's not how paths are meant to be used - the string arguments should be file- or directory names, not path fragments. #* creates a relative path (it's meant to be similar mnemonically to ./parent/child, while #/ creates an absolute path.

indeed this is cool. I was trying to find what you tried to express because I was sure that there was something like that But I was already reading it as star and not dot :) With dot and slash it makes a lot more sense.

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(FSPath * 'parent' / 'child') isRelative "true" (FSPath / 'parent' / 'child') isAbsolute "true"

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I saw that there is readFrom: aStream delimiter: aCharacter

so I created an unchecking instance creation category and I added with: and * in it.

It's not a matter of checked and unchecked so much as parsed and unparsed. #/ and #* provide a mini-DSL for building up paths, while #readFrom:delimiter: parses path strings.

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3- Then finally the following confuses me

(FSPath with: 'parent/child/') isRelative true

That creates to a relative path to a file/directory called 'parent/child'. In bash you'd escape the slashes like this:

parent\/child\/

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(FSPath with: '/parent/child/') isRelative true

That's a relative path to '/parent/child'. In bash: /\parent\/child\/

I was not aware of relative path starting with / Ugly bash.

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(FSPath with: '') isRelative false

That's an absolute path to the root of the file system. Absolute paths have an empty first element. If you consider $/ the a separator, '/usr/local/bin' has an empty first element, right?

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Either with: create relative path or isRelative is not consistent. If with: creates relative path then the last one should be true or isRelative should return false on the second one. ?

Ok, it's a bit of an unusual case, but I think it's important to be able to represent paths like \/parent\/child. Their perfectly valid as far as the filesystem is concerned, and we want to be able to work with such oddly-named files.

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4 - about FSPath root we have

root "Return the relative root path" ^ self with: ''

FSPath root returns / and I like that

Now what about defining root as

root ^ self with: '/'

It would be more consistent. Now it breaks everything. So I did not do it :)

I suppose that, strictly speaking, the most consistent way to represent the root directory is

root ^ self withAll: #('' '')

It still ends up being a bit of a special case, though.

Colin