An R client for the C library jq
Low-level
Low level interface, in which you can execute `jq` code just as you
would on the command line. Available via jq
High-level DSL
High-level, uses a suite of functions to construct queries. Queries
are constucted, then excuted internally with jq
NSE and SE
Most DSL functions have NSE (non-standard evaluation) and SE
(standard evaluation) versions, which make jqr easy to use
for interactive use as well as programming.
jq version
We link to jq through the installed version on your system,
so the version can vary. Run jq --version to get your jq version
indexing
note that jq indexing starts at 0, whereas R indexing
starts at 1. So when you want the first thing in an array using
jq, for example, you want 0, not 1
output data format
Note that with both the low level interface and the high level DSL, we
print the output to look like a valid JSON object to make it easier to
look at. However, it's important to know that the output is really just a
simple character string or vector of strings - it's just the print function
that pretty prints it and makes it look like a single JSON object. What jq
is giving you often is a stream of valid JSON objects, each one of which is
valid, but altogether are not valid. However, a trick you can do is to
wrap your jq program in brackets like [.[]] instead of .[]
to give a single JSON object
Related to above, you can use the function provided string
with the high level DSL to get back a character string instead of
pretty printed version