index and related functions

index and related functions

Usage

index(.data, ...)

index_(.data, ..., .dots)

indexif(.data, ...)

indexif_(.data, ..., .dots)

dotindex(.data, ...)

dotindex_(.data, ..., .dots)

Arguments

.data

input. This can be JSON input, or an object of class jqr that has JSON and query params combined, which is passed from function to function when using the jqr DSL.

...

Comma separated list of unquoted variable names

.dots

Used to work around non-standard evaluation

dots

dots

Details

• index/index_ - queries like: .[], .[0], .[1:5], .["foo"]

• indexif/indexif_ - queries like: .["foo"]?

• dotindex/dotindex_ - queries like: .[].foo, .[].foo.bar

Examples

str <- '[{"name":"JSON", "good":true}, {"name":"XML", "good":false}]'
str %>% index
#> [
#>     {
#>         "name": "JSON",
#>         "good": true
#>     },
#>     {
#>         "name": "XML",
#>         "good": false
#>     }
#> ]
'{"name":"JSON", "good":true}' %>% indexif(name)
#> "JSON"
'{"name":"JSON", "good":true}' %>% indexif(good)
#> true
'{"name":"JSON", "good":true}' %>% indexif(that)
#> null
'{"a": 1, "b": 1}' %>% index
#> [
#>     1,
#>     1
#> ]
'[]' %>% index
#> [
#> 
#> ]
'[{"name":"JSON", "good":true}, {"name":"XML", "good":false}]' %>% index(0)
#> {
#>     "name": "JSON",
#>     "good": true
#> }
'["a","b","c","d","e"]' %>% index(2)
#> "c"
'["a","b","c","d","e"]' %>% index('2:4')
#> [
#>     "c",
#>     "d"
#> ]
'["a","b","c","d","e"]' %>% index('2:5')
#> [
#>     "c",
#>     "d",
#>     "e"
#> ]
'["a","b","c","d","e"]' %>% index(':3')
#> [
#>     "a",
#>     "b",
#>     "c"
#> ]
'["a","b","c","d","e"]' %>% index('-2:')
#> [
#>     "d",
#>     "e"
#> ]

str %>% index %>% select(bad = .name)
#> [
#>     {
#>         "name": "JSON",
#>         "good": true
#>     },
#>     {
#>         "name": "XML",
#>         "good": false
#>     }
#> ]

'[{"name":"JSON", "good":true}, {"name":"XML", "good":false}]' %>%
  dotindex(name)
#> [
#>     "JSON",
#>     "XML"
#> ]
'[{"name":"JSON", "good":true}, {"name":"XML", "good":false}]' %>%
  dotindex(good)
#> [
#>     true,
#>     false
#> ]
'[{"name":"JSON", "good":{"foo":5}}, {"name":"XML", "good":{"foo":6}}]' %>%
  dotindex(good)
#> [
#>     {
#>         "foo": 5
#>     },
#>     {
#>         "foo": 6
#>     }
#> ]
'[{"name":"JSON", "good":{"foo":5}}, {"name":"XML", "good":{"foo":6}}]' %>%
  dotindex(good.foo)
#> [
#>     5,
#>     6
#> ]