Search, replace, and diff Elixir code by AST pattern.

Patterns are valid Elixir syntax:

• Variables (name, expr) capture matched nodes
• _ and _name are wildcards
• Structs/maps match partially
• Pipes are normalized (data |> Enum.map(f) matches Enum.map(data, f))
• Everything else matches literally
• CSS-like selectors can be built with ExAST.Selector

Options

• :inside — only match nodes inside an ancestor matching this pattern
• :not_inside — reject nodes inside an ancestor matching this pattern

Examples

# Find all IO.inspect calls
ExAST.search("lib/**/*.ex", "IO.inspect(_)")

# Find IO.inspect only inside test blocks
ExAST.search("test/", "IO.inspect(_)", inside: "test _ do _ end")

# Replace dbg with the expression itself
ExAST.replace("lib/**/*.ex", "dbg(expr)", "expr")

# Match piped and direct calls interchangeably
ExAST.search("lib/", "Enum.map(_, _)")  # also finds `data |> Enum.map(f)`

# Relationship-aware queries
import ExAST.Query

query =
  from("def _ do ... end")
  |> where(contains("Repo.transaction(_)"))
  |> where(not contains("IO.inspect(...)"))

ExAST.search("lib/", query)

# Capture guards — filter on captured values with ^pin
import ExAST.Query

query =
  from("Enum.take(_, count)")
  |> where(match?({:-, _, [_]}, ^count))

ExAST.search("lib/", query)

# Syntax-aware diff
result = ExAST.diff(old_source, new_source)
result.edits  #=> [%ExAST.Diff.Edit{op: :update, kind: :function, ...}]
ExAST.diff_files("lib/old.ex", "lib/new.ex")