get multiline data in parantheses without regex

Question

I am trying to parse go metafiles in the format of following:

require (
    github.com/cheggaaa/pb v1.0.28
    github.com/coreos/go-semver v0.2.0 // indirect
    github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e // indirect
    github.com/dustin/go-humanize v1.0.0
    github.com/fatih/color v1.7.0
        ...
        )

how do I get data between brackets and without using a regexp? (otherwise this noobish question would not exist at all). I have tried playing with split() but failed so far.

Maybe `[l.strip() for l in file.readlines()[1:-1]]`? Assumes it's formatted just like your example — rdas, Apr 20 '19 at 20:25
Can't understand what are you trying? Could you explain i/o? — jayprakashstar, Apr 20 '19 at 20:37
@PeterWood because it would be overkill? (see - besides others - your own answer... :) — SpghttCd, Apr 20 '19 at 20:53
@SpghttCd a simple regex could catch more errors, and explicitly encode assumptions about the format that my code doesn't communicate. — Peter Wood, Apr 20 '19 at 21:02

score 1 · Answer 1 · answered Apr 20 '19 at 20:36

1

@rdas's suggestion of [l.strip() for l in file.readlines()[1:-1]] will work if the metafile is formatted like your example is. But really, you should just use regex. It's easier.

answered Apr 20 '19 at 20:36

Alec

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score 0 · Answer 2 · answered Apr 20 '19 at 20:39

You can read the entire contents, split it into separate lines, then slice off the first and last lines:

with open(metafile) as f:
    requirements = f.read().splitlines()[1:-1]

Using with to open a file ensures it is closed properly when the scope ends.

score 0 · Answer 3 · answered Apr 20 '19 at 20:49

Here is a code that should do it. It will copy all the lines between 'requiere (' and ')' as long as there are no other ')' in those blocks.

data file:

random stuff
require (
    github.com/cheggaaa/pb v1.0.28
    github.com/coreos/go-semver v0.2.0 // indirect
    github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e //indirect
    github.com/dustin/go-humanize v1.0.0
    github.com/fatih/color v1.7.0
        ...
        )



random stuff

out file :

github.com/cheggaaa/pb v1.0.28
github.com/coreos/go-semver v0.2.0 // indirect
github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e //indirect
github.com/dustin/go-humanize v1.0.0
github.com/fatih/color v1.7.0
    ...

code :

f = open('data', 'r')
f2 = open('out', 'w')

toggle = False

for line in f:
    if 'require (' in line:
        toggle = True
        continue
    if toggle:
        if ')' in line:
            toggle = False
        else:
            f2.write(line)

f.close()
f2.close()

get multiline data in parantheses without regex

3 Answers3