Improve StatsStep and specset

Author: junyuan-chen

Project.toml

@@ -12,7 +12,6 @@ SplitApplyCombine = "03a91e81-4c3e-53e1-a0a4-9c0c8f19dd66"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
 StatsModels = "3eaba693-59b7-5ba5-a881-562e759f1c8d"
 Tables = "bd369af6-aec1-5ad0-b16a-f7cc5008161c"
-TypedTables = "9d95f2ec-7b3d-5a63-8d20-e2491e220bb9"
 
 [compat]
 CSV = "0.8"
@@ -23,7 +22,6 @@ SplitApplyCombine = "1.1"
 StatsBase = "0.33"
 StatsModels = "0.6.18"
 Tables = "1.2"
-TypedTables = "1.2"
 julia = "1.3"
 
 [extras]

src/DiffinDiffsBase.jl

@@ -9,10 +9,9 @@ using StatsBase
 using StatsModels: TupleTerm
 using SplitApplyCombine: groupfind, groupview
 using Tables: columntable, istable, rows, columns, getcolumn
-using TypedTables: Table
 
 import Base: ==, show, union
-import Base: eltype, firstindex, lastindex, getindex, iterate, length
+import Base: eltype, firstindex, lastindex, getindex, iterate, length, sym_in
 
 import StatsModels: termvars
 
@@ -56,12 +55,14 @@ export @fieldequal,
        parse_treat,
 
        StatsStep,
+       namedargs,
        AbstractStatsProcedure,
        SharedStatsStep,
        PooledStatsProcedure,
        pool,
        StatsSpec,
        @specset,
+       proceed,
 
        CheckData,