diff options
| -rw-r--r-- | ChangeLog | 14 | ||||
| -rw-r--r-- | eval.c | 1 | ||||
| -rw-r--r-- | lib.c | 34 | ||||
| -rw-r--r-- | lib.h | 1 | ||||
| -rw-r--r-- | txr.1 | 20 |
5 files changed, 67 insertions, 3 deletions
@@ -1,5 +1,19 @@ 2014-03-23 Kaz Kylheku <kaz@kylheku.com> + * eval.c (eval_init): Register empty as intrinsic. + + * lib.c (copy): Bugfix: handle lazy strings. Also, handle hash + tables via copy_hash. + (length): Bugifx: handle lazy strings. Also, handle hash tables + via hash_count. + (empty): New function. + + * lib.h (empty): Declared. + + * txr.1: Documented. + +2014-03-23 Kaz Kylheku <kaz@kylheku.com> + * eval.c (not_s): New symbol var. (me_unless, me_while, m_until): New static functions. (eval_init): Register macros unless, while and until. @@ -3527,6 +3527,7 @@ void eval_init(void) reg_fun(intern(lit("set-diff"), user_package), func_n4o(set_diff, 2)); reg_fun(intern(lit("length"), user_package), func_n1(length)); + reg_fun(intern(lit("empty"), user_package), func_n1(empty)); reg_fun(intern(lit("copy"), user_package), func_n1(copy)); reg_fun(intern(lit("sub"), user_package), func_n3o(sub, 1)); reg_fun(intern(lit("ref"), user_package), func_n2(ref)); @@ -4932,9 +4932,14 @@ val copy(val seq) return copy_list(seq); case LIT: case STR: + case LSTR: return copy_str(seq); case VEC: return copy_vec(seq); + case COBJ: + if (seq->co.cls == hash_s) + return copy_hash(seq); + /* fallthrough */ default: type_mismatch(lit("copy: ~s is not a sequence"), seq, nao); } @@ -4950,14 +4955,43 @@ val length(val seq) return length_list(seq); case LIT: case STR: + case LSTR: return length_str(seq); case VEC: return length_vec(seq); + case COBJ: + if (seq->co.cls == hash_s) + return hash_count(seq); + /* fallthrough */ default: type_mismatch(lit("length: ~s is not a sequence"), seq, nao); } } +val empty(val seq) +{ + switch (type(seq)) { + case NIL: + return t; + case CONS: + case LCONS: + return nil; + case LIT: + case STR: + return if2(c_str(seq)[0] == 0, t); + case LSTR: + return length_str_le(seq, zero); + case VEC: + return eq(length_vec(seq), zero); + case COBJ: + if (seq->co.cls == hash_s) + return eq(hash_count(seq), zero); + /* fallthrough */ + default: + type_mismatch(lit("empty: ~s is not a sequence"), seq, nao); + } +} + val sub(val seq, val from, val to) { switch (type(seq)) { @@ -712,6 +712,7 @@ val pos_if(val pred, val list, val key); val set_diff(val list1, val list2, val testfun, val keyfun); val copy(val seq); val length(val seq); +val empty(val seq); val sub(val seq, val from, val to); val ref(val seq, val ind); val refset(val seq, val ind, val newval); @@ -9727,7 +9727,20 @@ Syntax: Description: The length function returns the number of items in <sequence>, and -returns it. +returns it. <sequence> may be a hash, in which case (hash-count <sequence>) is +returned. + +.SS Function empty + +.TP +Syntax: + + (empty <sequence>) + +.TP +Description: + +Returns t if (length <sequence>) is zero, otherwise nil. .SS Function copy @@ -9741,8 +9754,9 @@ Description: The copy function duplicates a sequence. If <sequence> is nil, it returns nil. If <sequence> is a list, it returns (copy-list <sequence>); -if <sequence> is a string, it returns (copy-str <sequence>); and -if <sequence> is a vector, it returns (copy-vec <sequence>). +if <sequence> is a string, it returns (copy-str <sequence>); +if <sequence> is a vector, it returns (copy-vec <sequence>); and +if <sequence> is a hash, it return (copy-hash <sequence>). Except in the case when <sequence> is nil, copy returns a value that is distinct from (not eq to) <sequence>. This is different from |