CodeQL library for JavaScript/TypeScript
codeql/javascript-all 1.0.3-dev (changelog, source)

Member predicate BasicBlock::isLiveAtEntry

Holds if v is live at entry to this basic block and u is a use of v witnessing the liveness.

In other words, u is a use of v that is reachable from the entry node of this basic block without going through a redefinition of v. The use u may either be in this basic block, or in another basic block reachable from this one.

predicate isLiveAtEntry(Variable v, VarUse u)