blog

Suppose we want to clean up all TODOs in a branch before merging. We can check for TODOs introduced with

git diff master | rg '(\+|-).*TODO'

Thence:

, opt_inlineWFCacheLimit  = 10 -- TODO: find "optimal" value
, opt_inlineWFCacheLimit      = 10 -- TODO: find "optimal" value
-- TODO The RewriteEnv should just take ClashOpts.
-- TODO This was a call to makeCachedU, but since there was no variation
-- TODO Should tm3 be done async / added to the job queue when it's made?
-- TODO Given we now keep transformCounters, this should just be 'fold'
-- TODO Although we're locking access to the history file, entries
+-- TODO I think isWorkFree only needs to exist within the rewriting monad, and

However this is inconvenient; it strips file names and line numbers, making whatever one uncovers harder to address.

One can handle this with Awk but I think it is instructive to use Jacinda here, both to show how to do this in a functional style and to face Jacinda's limitations.

We will create an expression that is capable of tracking state across lines using a scan, viz.

@include'prelude/fn.jac'
@include'lib/maybe.jac'
fn mMatch(str, re) :=
  if str ~ re
    then Some str
    else None;
fn step(needle, ctx, line) :=
  let
    val fpCtx ≔ line ~* 1 /diff --git\s+([^\s]+)/
    val mLine ≔ mMatch line needle
  in (alternative (ctx->1) fpCtx.mLine) end;
fn process(x) :=
  let
    val fpCtx ≔ fromMaybe 'WARN' (x->1)
    val line ≔ (λl. sprintf'%s: %s' (fpCtx.l))"(x->2)
  in line end;
process:?(step/(\+|-).*TODO/)^(None.None)$0

Note that we need lib/maybe.dck for alternative, Haskell's (<|>).

We get:

clash-lib/src/Clash/Driver/Types.hs: -  , opt_inlineWFCacheLimit  = 10 -- TODO: find "optimal" value
clash-lib/src/Clash/Driver/Types.hs: +  , opt_inlineWFCacheLimit      = 10 -- TODO: find "optimal" value
clash-lib/src/Clash/Normalize.hs: -    -- TODO The RewriteEnv should just take ClashOpts.
clash-lib/src/Clash/Normalize/Util.hs: +  -- TODO This was a call to makeCachedU, but since there was no variation
clash-lib/src/Clash/Normalize/Util.hs: +      -- TODO Should tm3 be done async / added to the job queue when it's made?
clash-lib/src/Clash/Rewrite/Types.hs: -    -- TODO Given we now keep transformCounters, this should just be 'fold'
clash-lib/src/Clash/Rewrite/Util.hs: +          -- TODO Although we're locking access to the history file, entries
clash-lib/src/Clash/Rewrite/WorkFree.hs: +-- TODO I think isWorkFree only needs to exist within the rewriting monad, and

My guess is that this is more prolix than the equivalent in Awk. Moreover, Jacinda suffers from the lack of user-defined operators; I would like ~? in place of mMatch and something like <|> in place of alternative.