## Logiweb aspects of tactic-at2 ( " , " , " , " , " ) in pyk

### The "pyk" aspect

Define pyk of tactic-at2 ( asterisk , asterisk , asterisk , asterisk , asterisk ) as "tactic-at2 ( "! , "! , "! , "! , "! )" end define

### The "value" aspect

define value of tactic-at2 ( t , s , v , s prime , c ) as norm { t is val : { s is val : { v is val : { s prime is val : { c is val : if v then s [[ hook-res -> metasubst ( s [[ hook-res ]] , s prime , c ) ]] else LET v BE { asterisk IN LET { if asterisk atom then asterisk else { asterisk head } } :: { { if asterisk atom then asterisk else { asterisk tail } } :: true } BE { asterisk prime IN LET asterisk prime head BE { asterisk IN LET asterisk prime tail BE { asterisk prime IN LET asterisk BE { y IN LET asterisk prime head BE { asterisk IN LET asterisk prime tail BE { asterisk prime IN LET asterisk BE { v IN LET make-root ( t , quote s [[ hook-arg ]] unquote at { y unquote } end quote ) :: { s [[ hook-arg ]] :: { y :: true } } BE { asterisk IN LET asterisk BE { a IN LET s [[ hook-res ]] BE { asterisk IN LET asterisk BE { r IN if mismatch ( quote All x : y end quote , r , c ) then error ( t , diag ( "At tactic used on non-quantifier:" ) disp ( r ) end diagnose ) else LET s [[ hook-arg -> a ]] [[ hook-res -> r second ]] BE { asterisk IN LET asterisk BE { s IN tactic-at2 ( t , s , v , { r first :: y } :: { s prime } , c ) } } } } } } } } } } } } } } } } } } } end define

The pyk compiler, version 0.1.9 by Klaus Grue,
GRD-2007-07-12.UTC:20:11:58.175987 = MJD-54293.TAI:20:12:31.175987 = LGT-4690987951175987e-6