Operations on keys, or by keys

keys takes no input, and retrieves keys. del deletes provided keys. haskey checks if a json string has a key, or the input array has an element at the given index.

Usage

keys(.data)

del(.data, ...)

del_(.data, ..., .dots)

haskey(.data, ...)

haskey_(.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

Examples

# get keys
str <- '{"foo": 5, "bar": 7}'
jq(str, "keys")
#> [
#>     "bar",
#>     "foo"
#> ]
str %>% keys()
#> [
#>     "bar",
#>     "foo"
#> ]

# delete by key name
jq(str, "del(.bar)")
#> {
#>     "foo": 5
#> }
str %>% del(bar)
#> {
#>     "foo": 5
#> }

# check for key existence
str3 <- '[[0,1], ["a","b","c"]]'
jq(str3, "map(has(2))")
#> [
#>     false,
#>     true
#> ]
str3 %>% haskey(2)
#> [
#>     false,
#>     true
#> ]
jq(str3, "map(has(1,2))")
#> [
#>     true,
#>     false,
#>     true,
#>     true
#> ]
str3 %>% haskey(1,2)
#> [
#>     true,
#>     false,
#>     true,
#>     true
#> ]

## many JSON inputs
'{"foo": 5, "bar": 7} {"hello": 5, "world": 7}' %>% keys
#> [
#>     [
#>         "bar",
#>         "foo"
#>     ],
#>     [
#>         "hello",
#>         "world"
#>     ]
#> ]
'{"foo": 5, "bar": 7} {"hello": 5, "bar": 7}' %>% del(bar)
#> [
#>     {
#>         "foo": 5
#>     },
#>     {
#>         "hello": 5
#>     }
#> ]