Set Local LM Override

Sets a scoped LLM override that lasts until the calling function exits. Useful for functions that need to ensure a specific LLM is used for all internal dsprrr calls.

Usage

local_lm(lm, .env = parent.frame())

Arguments

lm

An ellmer Chat object to use as the default LLM, or NULL to clear any scoped override.

.env

The environment to scope to (defaults to caller's environment).

Value

Invisibly returns the previous scoped LM (if any).

Details

This function uses withr::defer() to ensure cleanup when the calling function exits, even if an error occurs. For a block-based alternative, see with_lm().

Examples

if (FALSE) { # \dontrun{
my_analysis <- function(data) {
  # All dsprrr calls in this function will use Claude
  local_lm(ellmer::chat_claude())

  # These calls don't need .llm parameter
  summary <- run(module(signature("data -> summary")), data = data)
  insights <- run(
    module(signature("summary -> insights")),
    summary = summary
  )
  insights
}

# The scoped LM is automatically cleared when my_analysis() returns
result <- my_analysis(my_data)
} # }