1. comment removal.
I wanted to be able to remove line comments from various source code but also
keep the block style comments and headers intact.
Here is a snipet that i've adapted from my other code to do just that.
---------------------------------------------------------------
object x -- An object placeholder for various data types
integer i -- An integer variable 
constant
COMMENT = "--",
INPUT = -- ADD FIELMANE HERE!
OUTPUT = -- ADD FILENAME HERE!
constant Fn = open("INPUT" , "r")
constant Tn = open("OUTPUT", "w")
constant S = COMMENT
-- get line's ( inludes '\n' char ) for proccessing
while 1 do
x = gets(Fn)
if atom(x) then -- -1 is returned at EOF
exit -- done!
else
i = match(S, x) -- look for line comment
end if
-- if comment is found at end of line we remove it!
if ( i > 1 ) then
x = x[1..i - 1] -- trims off the comment
end if
-- makes sure the line is terminated with '\n' char
if x[$] != '\n' then -- there's no '\n' char!
x &= '\n' -- fix it up!
end if
-- Ok, writes the modified line out to the tempfile
if equal(repeat(' ', length(x) - 1) & '\n', x)
then
-- just an empty sequence - so do nothing!
else
puts(Tn, x)
end if
end while
2. Re: comment removal.
Hi
Why not put this in euwiki - too small for a submission, but useful enough to be
kept for posterity and reference.
Chris
===================================================================================
There is a train of thought that a generalist knows a little about a lot of
things,
and that a specialist knows a lot about very little.
If you took this to the extreme, you could become so specialised so as to know
everything there was to know about nothing.
===================================================================================
http://euallegro.wikispaces.com
http://members.aol.com/chriscrylex/euphoria.htm
http://uboard.proboards32.com/
http://members.aol.com/chriscrylex/EUSQLite/eusql.html
3. Re: comment removal.
Chris Burch wrote:
>
> Hi
>
> Why not put this in euwiki - too small for a submission, but useful enough to
> be kept for posterity and reference.
>
> Chris
>
>
> ===================================================================================
> There is a train of thought that a generalist knows a little about a lot of
> things,
> and that a specialist knows a lot about very little.
> If you took this to the extreme, you could become so specialised so as to know
> everything there was to know about nothing.
>
> ===================================================================================
>
> <a href="http://euallegro.wikispaces.com">http://euallegro.wikispaces.com</a>
> <a
> href="http://members.aol.com/chriscrylex/euphoria.htm">http://members.aol.com/chriscrylex/euphoria.htm</a>
> <a href="http://uboard.proboards32.com/">http://uboard.proboards32.com/</a>
> <a
> href="http://members.aol.com/chriscrylex/EUSQLite/eusql.html">http://members.aol.com/chriscrylex/EUSQLite/eusql.html</a>
Problem with that piece of code is that, if a quoted string contains the
"--" substring, the remainder of the line will be deleted. Could be a
nuisance.
CChris
4. Re: comment removal.
CChris wrote:
>
> Chris Burch wrote:
> >
> > Hi
> >
> > Why not put this in euwiki - too small for a submission, but useful enough
> > to
> > be kept for posterity and reference.
> >
> > Chris
> >
> >
> > ===================================================================================
> > There is a train of thought that a generalist knows a little about a lot of
> > things,
> > and that a specialist knows a lot about very little.
> > If you took this to the extreme, you could become so specialised so as to
> > know
> > everything there was to know about nothing.
> >
> > ===================================================================================
> >
> > <a
> > href="http://euallegro.wikispaces.com">http://euallegro.wikispaces.com</a>
> > <a
> > href="http://members.aol.com/chriscrylex/euphoria.htm">http://members.aol.com/chriscrylex/euphoria.htm</a>
> > <a href="http://uboard.proboards32.com/">http://uboard.proboards32.com/</a>
> > <a
> > href="http://members.aol.com/chriscrylex/EUSQLite/eusql.html">http://members.aol.com/chriscrylex/EUSQLite/eusql.html</a>
>
> Problem with that piece of code is that, if a quoted string contains the
> "--" substring, the remainder of the line will be deleted. Could be a
> nuisance.
>
> CChris
Origionaly I had to remove "//" comments from hundreds and thousands of lines of
sourcecode, and that piece of code did the trick.
I thought about adding command line and prompt support and checking for various
other cases but there was no need to do that at the time.
The code snippet did it's job and then got filed away, and probably never to be
used again by me.
Anyone is welcome to modify or complete the code for there needs. If you do, I
ask that you please share it with others.
5. Re: comment removal.
Hayden McKay wrote:
>
> CChris wrote:
> >
> > Chris Burch wrote:
> > >
> > > Hi
> > >
> > > Why not put this in euwiki - too small for a submission, but useful enough
> > > to
> > > be kept for posterity and reference.
> > >
> > > Chris
> > >
> > >
> > > ===================================================================================
> > > There is a train of thought that a generalist knows a little about a lot
> > > of
> > > things,
> > > and that a specialist knows a lot about very little.
> > > If you took this to the extreme, you could become so specialised so as to
> > > know
> > > everything there was to know about nothing.
> > >
> > > ===================================================================================
> > >
> > > <a
> > > href="http://euallegro.wikispaces.com">http://euallegro.wikispaces.com</a>
> > > <a
> > > href="http://members.aol.com/chriscrylex/euphoria.htm">http://members.aol.com/chriscrylex/euphoria.htm</a>
> > > <a
> > > href="http://uboard.proboards32.com/">http://uboard.proboards32.com/</a>
> > > <a
> > > href="http://members.aol.com/chriscrylex/EUSQLite/eusql.html">http://members.aol.com/chriscrylex/EUSQLite/eusql.html</a>
> >
> > Problem with that piece of code is that, if a quoted string contains the
> > "--" substring, the remainder of the line will be deleted. Could be a
> > nuisance.
> >
> > CChris
>
> Origionaly I had to remove "//" comments from hundreds and thousands of lines
> of sourcecode, and that piece of code did the trick.
>
> I thought about adding command line and prompt support and checking for
> various
> other cases but there was no need to do that at the time.
>
> The code snippet did it's job and then got filed away, and probably never to
> be used again by me.
>
> Anyone is welcome to modify or complete the code for there needs. If you do,
> I ask that you please share it with others.
Hi
In other words, the perfect job for euwiki - code development by evolution
Unless you have any objections, I'll put it up there.
Chris
6. Re: comment removal.
ChrisBurch2 wrote:
>
> In other words, the perfect job for euwiki - code development by evolution
Nothing has evolved here. It's all been intelligently designed. :D
7. Re: comment removal.
Hayden McKay wrote:
>
> CChris wrote:
> >
> > Chris Burch wrote:
> > >
> > > Hi
> > >
> > > Why not put this in euwiki - too small for a submission, but useful enough
> > > to
> > > be kept for posterity and reference.
> > >
> > > Chris
> > >
> > >
> > > ===================================================================================
> > > There is a train of thought that a generalist knows a little about a lot
> > > of
> > > things,
> > > and that a specialist knows a lot about very little.
> > > If you took this to the extreme, you could become so specialised so as to
> > > know
> > > everything there was to know about nothing.
> > >
> > > ===================================================================================
> > >
> > > <a
> > > href="http://euallegro.wikispaces.com">http://euallegro.wikispaces.com</a>
> > > <a
> > > href="http://members.aol.com/chriscrylex/euphoria.htm">http://members.aol.com/chriscrylex/euphoria.htm</a>
> > > <a
> > > href="http://uboard.proboards32.com/">http://uboard.proboards32.com/</a>
> > > <a
> > > href="http://members.aol.com/chriscrylex/EUSQLite/eusql.html">http://members.aol.com/chriscrylex/EUSQLite/eusql.html</a>
> >
> > Problem with that piece of code is that, if a quoted string contains the
> > "--" substring, the remainder of the line will be deleted. Could be a
> > nuisance.
> >
> > CChris
>
> Origionaly I had to remove "//" comments from hundreds and thousands of lines
> of sourcecode, and that piece of code did the trick.
>
> I thought about adding command line and prompt support and checking for
> various
> other cases but there was no need to do that at the time.
>
> The code snippet did it's job and then got filed away, and probably never to
> be used again by me.
>
> Anyone is welcome to modify or complete the code for there needs. If you do,
> I ask that you please share it with others.
Ok...
After removing the quotes around INPUT and OUTPUT, since they cause a bad
file number (-1) to be reported, I fed a
file containing
sequence s
s="this line has -- inside it"
to the code in the original post.
The output file had:
sequence s
s="this line has
, which I expected from reading the code.
file 1 compiles correctly, file 2 bombs out. This is not expected when
changing/adding/removing comments.
I remember having trouble writing an uncomment function for my enhanced
version of Visual Euphoria (Joe aka spent_memory). I'll dig up the code
and post it. It is definitively longer, but does the job. This is because
not only you have to take care of (multiple) string(s) inside any given line,
but locating where they start/end is made trickier if escaped double quotes
are there as well.
There are two options basically:
1/locate and mask the strings which are not inside a comment, then use
match(COMMENT,line) and truncate original line;
2/ work as scanner.e does, using a flag to detect whether it is inside a
string or not, plowing along the line and truncating it when COMMENT is
found outside a string.
I never investigated which approach is faster.
Next exercise: also auto uncomment /*...*/ embedded C comments 
CChris
8. Re: comment removal.
- Posted by CChris <christian.cuvier at agriculture.gouv.fr>
Mar 21, 2007
-
Last edited Mar 22, 2007
[snipped]
> >
> > Origionaly I had to remove "//" comments from hundreds and thousands of
> > lines
> > of sourcecode, and that piece of code did the trick.
> >
> > I thought about adding command line and prompt support and checking for
> > various
> > other cases but there was no need to do that at the time.
> >
> > The code snippet did it's job and then got filed away, and probably never to
> > be used again by me.
> >
> > Anyone is welcome to modify or complete the code for there needs. If you do,
> > I ask that you please share it with others.
>
> Ok...
> After removing the quotes around INPUT and OUTPUT, since they cause a bad
> file number (-1) to be reported, I fed a
> file containing
>
> }}}
<eucode>
> sequence s
> s="this line has -- inside it"
> </eucode>
{{{
> to the code in the original post.
>
> The output file had:
> }}}
<eucode>
> sequence s
> s="this line has
> </eucode>
{{{
> , which I expected from reading the code.
>
> file 1 compiles correctly, file 2 bombs out. This is not expected when
> changing/adding/removing comments.
>
> I remember having trouble writing an uncomment function for my enhanced
> version of Visual Euphoria (Joe aka spent_memory). I'll dig up the code
> and post it. It is definitively longer, but does the job. This is because
> not only you have to take care of (multiple) string(s) inside any given line,
> but locating where they start/end is made trickier if escaped double quotes
> are there as well.
>
> There are two options basically:
> 1/locate and mask the strings which are not inside a comment, then use
> match(COMMENT,line) and truncate original line;
> 2/ work as scanner.e does, using a flag to detect whether it is inside a
> string or not, plowing along the line and truncating it when COMMENT is
> found outside a string.
> I never investigated which approach is faster.
>
> Next exercise: also auto uncomment /*...*/ embedded C comments
>
> CChris
I added the parity backslash twist, so more tests may be needed:
function evenBackslashes(sequence s,integer q)
-- returns 1 if the number of contiguous backslash chars right before the double
quote is even
-- assert s[q]=34
q-=1
for i=q to 1 by -1 do
if s[i]!='\\' then
return not and_bits(xor_bits(q,i),1)
end if
end for
return not and_bits(q,1)
end function
function findMatchingDQ(sequence s,integer q)
-- returns position in s of the double quote matching s[q-1]
integer p
while 1 do
p=find('"',s[q..length(s)])
if not p then return 0 end if -- none found
q+=p
if evenBackslashes(s,q-1) then return q-1 end if
s[q-1]=0 -- mask and try again
end while
end function
global function removeComment(sequence s)
-- determines whether s has a comment mark, and strips the tail , starting at
the mark.
integer p,q
sequence sofar,s0
sofar=""
s0=s puts(1,s&'\n')
while 1 do
p=match("--",s)
if not p then return sofar & s end if
while 1 do
q=find('"',s)
if not q or q>p then return sofar & s[1..p-1] end if
if evenBackslashes(s,q) then -- here starts a string
q=findMatchingDQ(s,q+1)
if not q then return s0 end if -- unclosed string
sofar &= s[1..q] -- accumulate valid part of s
s=s[q+1..length(s)]
if q>p then -- the comment mark is inside a string, start over
from end of string
exit
else
p-=q -- located mark may still be good
end if
else -- this is an escaped double quote, keep looking past it
sofar&=s[1..q] -- accumulate valid part of s
s=s[q+1..length(s)]
p-=q -- located mark may still be good
end if
end while
end while
end function
-- stress test
-- assume a file contains the line as displayed:
-- puts(1,"this -- is \" inside a string"&"perhaps"&"\\\\\\"&'\n')
-- puts(1,removeComment("puts(1,\"this -- is \\\" inside a
string\"&\"perhaps\"&\"\\\\\\\\\\\\\" ) -- not really"))
-- ?machine_func(26,0)
Input and bug reports appreciated.
CChris
9. Re: comment removal.
CChris wrote:
>
> [snipped]
>
> > >
> > > Origionaly I had to remove "//" comments from hundreds and thousands of
> > > lines
> > > of sourcecode, and that piece of code did the trick.
> > >
> > > I thought about adding command line and prompt support and checking for
> > > various
> > > other cases but there was no need to do that at the time.
> > >
> > > The code snippet did it's job and then got filed away, and probably never
> > > to
> > > be used again by me.
> > >
> > > Anyone is welcome to modify or complete the code for there needs. If you
> > > do,
> > > I ask that you please share it with others.
> >
> > Ok...
> > After removing the quotes around INPUT and OUTPUT, since they cause a bad
> > file number (-1) to be reported, I fed a
> > file containing
> >
> > }}}
<eucode>
> > sequence s
> > s="this line has -- inside it"
> > </eucode>
{{{
> > to the code in the original post.
> >
> > The output file had:
> > }}}
<eucode>
> > sequence s
> > s="this line has
> > </eucode>
{{{
> > , which I expected from reading the code.
> >
> > file 1 compiles correctly, file 2 bombs out. This is not expected when
> > changing/adding/removing comments.
> >
> > I remember having trouble writing an uncomment function for my enhanced
> > version of Visual Euphoria (Joe aka spent_memory). I'll dig up the code
> > and post it. It is definitively longer, but does the job. This is because
> > not only you have to take care of (multiple) string(s) inside any given
> > line,
> > but locating where they start/end is made trickier if escaped double quotes
> > are there as well.
> >
> > There are two options basically:
> > 1/locate and mask the strings which are not inside a comment, then use
> > match(COMMENT,line) and truncate original line;
> > 2/ work as scanner.e does, using a flag to detect whether it is inside a
> > string or not, plowing along the line and truncating it when COMMENT is
> > found outside a string.
> > I never investigated which approach is faster.
> >
> > Next exercise: also auto uncomment /*...*/ embedded C comments
> >
> > CChris
>
Submitted a comment remover. Hopefully, it copes with all cases, and tries
to be smart and not to generate too many blank lines. Look to nocoment.e.
CChris
10. Re: comment removal.
Just a thought...
what about scanning each line from R -> L, would it be any easier or
more efficiant than the the L -> R parser?
ps. Thankyou to CChris for his submission I'm about to give your
de-comment tool a go.
