Non-integer decimal numbers lose precision

[matthewdale]

Parsing a non-integer decimal number with more than about 16 digits will truncate the precision of the number to the what can be represented by a float64:

$ echo 0.123456789012345678901234567890 | gojq '. | tojson'
"0.12345678901234568"

In comparison, jq will preserve all of the decimal precision for non-arithmetic operations (e.g. . and tojson):

$ echo 0.123456789012345678901234567890 | jq '. | tojson'
"0.123456789012345678901234567890"

gojq currently supports arbitrary precision for integer values, including integer arithmetic operations. It would be great if it also supported arbitrary precision for non-integer decimal values for "passthrough" operations, and possibly arithmetic operations.

[itchyny]

This is related to the issue #212 and will be resolved by the json-number branch.

[wader]

@itchyny for clarity, that would solve the pass thru part but not doing operations?

For reference @matthewdale did a draft PR for decimal support in the fq fork wader#1 but i'm a bit reluctant to add more difference to upstream unless it can be done in a easy rebase-able and maintainable way