Search and replace with increment in vim - vim

Question

I have a json file which looks as follows:
{
"pk": 1,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
{
"pk": 1,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
{
"pk": 1,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
etc....
I would like to search and replace "pk": 1 and increment the value. so my file would look like:
{
"pk": 1,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
{
"pk": 2,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
{
"pk": 3,
"model": "model.Model",
"fields": {
"data1": "example",
"data2": "example"
}
},
So far I have tried:
:let i=1 | g/"pk": 1/s//="pk": .i./ | let i=i+1
to search for the "pk": 1 pattern and replace it using a counter, but I have a syntax error somewhere and am hitting a brick wall.
Any help / suggestions would be very much appreciated thanks.

Answer 1

You could try:
:let i=1 | g/"pk": \zs\d\+/ s//\=i/ | let i+=1
\zs .............. start pattern
To fix your attempt do:
:let i=1 | g/"pk": 1/s//\='"pk": ' .i/ | let i=i+1
As you can see the first mistake was a missing backslash at the substitution portion \=. The second was using a second concatenation at the end . which would make vim try to concatenate the variable with nothing. The third was forgetting to put the "pk": into 'single quotes' otherwise you would ended up with pk unquoted. Remember here we are concatenating a string with a number.