diff options
| -rw-r--r-- | stdlib/doc-syms.tl | 1 | ||||
| -rw-r--r-- | txr.1 | 30 |
2 files changed, 31 insertions, 0 deletions
diff --git a/stdlib/doc-syms.tl b/stdlib/doc-syms.tl index bb51d785..fff64b8a 100644 --- a/stdlib/doc-syms.tl +++ b/stdlib/doc-syms.tl @@ -54,6 +54,7 @@ ("*stdlog*" "N-00854995") ("*stdnull*" "N-006566FB") ("*stdout*" "N-006566FB") + ("*struct-clause-expander*" "N-0141A208") ("*trace-output*" "N-0067A6AC") ("*tree-fun-whitelist*" "N-025AB9C9") ("*unhandled-hook*" "N-02B4A4FB") @@ -31222,6 +31222,36 @@ or a subtype thereof. fa.(write 4) -> ;; error: fa has no such method .brev +.coNP Special variable @ *struct-clause-expander* +.desc +The +.code *struct-clause-expander* +special variable holds the hash table of associations between +keyword symbols and struct clause expander functions, defined by +.codn define-struct-clause . + +If the expression +.code "[*struct-clause-expander* :sym]" +yields a function, then symbol +.code :sym +has a binding as a struct clause macro. If that +expression yields +.codn nil , +then there is no such binding. + +The macro expanders in +.code *struct-clause-expander* +are two-parameter functions. The first parameter accepts the +clause to to be expanded. The second parameter accepts the +.code defstruct +form in which that clause is found; this is useful for error +reporting. + +An expander function returns a list of clauses, which may be any, possibly +empty mixture of primary clauses accepted by +.code defstruct +and clause macros. + .SS* Special Structure Functions Special structure functions are user-defined methods or structure functions |