pull: Creates pull expressions

In ParkerICI/datalogr: Interacting with a Datomic database via R

Description

This function creates Datomic pull expressions. The following rules apply when converting R expressions to Datomic pull expressions:

• Clojure vector literals (i.e. []) are represented as c() in R

• Clojure map literalas (i.e. {key val}) are represented as {key = val} in R

• Back references are specified by pre-prending a . to the attribute name (instead of a _). E.g. the Clojure variant/_gene becomes variant/.gene

• The wildcard pattern * is represented as . in R

• Strings containing the / character are assumed to represent qualified symbol names and are converted by pre-prending the : character. E.g. the Clojure :variant/gene becomes variant/gene

Usage

pull(...)

Arguments

...	This function takes exactly 2 arguments which must be specified in the following order (named arguments are not supported, the arguments are matched positionally) The variable representing the entity id from which the pull is initiated The pull expression

Value

Returns a data structure representing the pull expression, suitable for inclusion in the find clause of a query

Examples

qq <- query(
  find(pull(?s, c({sample/subject = c(.)}, .))),
  where(
    d(?s, sample/id, ?id)
  )
)
do_query(qq)

qq <- query(
  find(pull(?g, c(gene/hugo, {variant/.gene = c({variant/type = c(db/ident)}, .)})))
  where(
    d(?g, gene/hugo, ?hugo)
  )
)
do_query(qq)

ParkerICI/datalogr documentation built on Aug. 16, 2021, 10:59 a.m.