feat(rc): string join operator

8 files changed, 66 insertions, 24 deletions

diff --git a/sys/cmd/rc/code.c b/sys/cmd/rc/code.c
index 70fe818..46873ef 100644
--- a/sys/cmd/rc/code.c
+++ b/sys/cmd/rc/code.c
@@ -66,10 +66,10 @@ walk(Tree *node)
         emitf(Xcount);
         break;
 
-    case Tflat:
+    case Tjoin:
         emitf(Xmark);
         walk(node->child[0]);
-        emitf(Xflat);
+        emitf(Xjoin);
         break;
 
     case ';':
diff --git a/sys/cmd/rc/exec.c b/sys/cmd/rc/exec.c
index ac0dc08..425d00f 100644
--- a/sys/cmd/rc/exec.c
+++ b/sys/cmd/rc/exec.c
@@ -625,6 +625,47 @@ Xconcatenate(void)
 }
 
 void
+Xjoin(void)
+{
+    int  n;
+    char *s;
+    Word *arg, *elt;
+
+    if(count(runner->args->word) != 1){
+        Xerror("variable name is not singleton\n");
+        return;
+    }
+
+    s = runner->args->word->str;
+    // deglob(s)
+
+    arg = var(s)->val;
+    poplist();
+
+    n = count(arg);
+    if(n==0){
+        pushword("");
+        return;
+    }
+
+    for(elt = arg; elt; elt=elt->link)
+        n += strlen(elt->str);
+
+    s = emalloc(n);
+    if(arg){
+        strcpy(s, arg->str);
+        for(elt = arg->link; elt; elt = elt->link){
+            strcat(s, " ");
+            strcat(s, elt->str);
+        }
+    }else
+        s[0] = 0;
+
+    pushword(s);
+    efree(s);
+}
+
+void
 Xdollar(void)
 {
     int n;
diff --git a/sys/cmd/rc/exec.h b/sys/cmd/rc/exec.h
index d018fed..4bf2a4b 100644
--- a/sys/cmd/rc/exec.h
+++ b/sys/cmd/rc/exec.h
@@ -20,6 +20,7 @@ void Xasync(void);
 void Xbasic(void);     // Xbasic(args) run command and wait for result
 void Xsubshell(void);
 void Xword(void);
+void Xjoin(void);
 void Xconcatenate(void);
 void Xcount(void);
 void Xflat(void);
diff --git a/sys/cmd/rc/io.c b/sys/cmd/rc/io.c
index f033031..dc81c2e 100644
--- a/sys/cmd/rc/io.c
+++ b/sys/cmd/rc/io.c
@@ -230,7 +230,6 @@ printtree(Io *io, Tree *t)
     switch(t->type){
     default: print(io, "bad(%d)[%p %p %p]", t->type, C0, C1, C2); break;
     case '$': print(io,"$%t",C0);      break;
-    case '"': print(io,"\"%t",C0);     break;
     case '&': print(io,"%t&",C0);      break;
     case '^': print(io,"%t^%t",C0,C1); break;
     case '`': print(io,"`%t",C0);      break;
@@ -240,6 +239,7 @@ printtree(Io *io, Tree *t)
     case Tblock:    print(io, "{%t}", C0);  break;
     case Tcount:    print(io, "$#%t", C0);  break;
     case Tparen:    print(io, "(%t)", C0);  break;
+    case Tjoin:     print(io,"$\"%t",C0);   break;
     case Tindex:    print(io, "%t(%t)",C0); break;
     case Tsubshell: print(io, "@ %t",C0);   break;
     //case Ttwiddle:  print(io, "~ %t %t", C0, C1);  break;
diff --git a/sys/cmd/rc/lex.c b/sys/cmd/rc/lex.c
index 8ddf270..5de238e 100644
--- a/sys/cmd/rc/lex.c
+++ b/sys/cmd/rc/lex.c
@@ -217,6 +217,19 @@ yylex(void)
         put3('E','O','F');
         return EOF;
 
+    case '$':
+        lexer.haddollar = 1;
+        if(nextis('#')){
+            put2('$','#');
+            return Tcount;
+        }
+        if(nextis('^')){
+            put2('$','^');
+            return Tjoin;
+        }
+        put1('$');
+        return '$';
+
     case '@':
         lexer.haddollar = 0;
         put1('@');
@@ -324,19 +337,6 @@ yylex(void)
 
         return node->type;
 
-    case '$':
-        lexer.haddollar = 1;
-        if(nextis('#')){
-            put2('$','#');
-            return Tcount;
-        }
-        if(nextis('^')){
-            put2('$','^');
-            return Tflat;
-        }
-        put1('$');
-        return '$';
-
     case '\'':
         lexer.hadword   = 1;
         lexer.inquote   = 1;
diff --git a/sys/cmd/rc/parse.c b/sys/cmd/rc/parse.c
index 731c244..d1909a5 100644
--- a/sys/cmd/rc/parse.c
+++ b/sys/cmd/rc/parse.c
@@ -127,7 +127,7 @@ enum yysymbol_kind_t
   YYSYMBOL_22_ = 22,                       /* '^'  */
   YYSYMBOL_23_ = 23,                       /* '$'  */
   YYSYMBOL_Tcount = 24,                    /* Tcount  */
-  YYSYMBOL_Tflat = 25,                     /* Tflat  */
+  YYSYMBOL_Tjoin = 25,                     /* Tjoin  */
   YYSYMBOL_26_ = 26,                       /* '('  */
   YYSYMBOL_27_ = 27,                       /* ')'  */
   YYSYMBOL_28_ = 28,                       /* '{'  */
@@ -567,7 +567,7 @@ static const char *const yytname[] =
   "\"end of file\"", "error", "\"invalid token\"", "Tword", "Twords",
   "Tif", "Telse", "Tbang", "Tsubshell", "Toror", "Tandand", "There",
   "Tredir", "Tpipe", "Tdup", "Tbasic", "Tparen", "Tblock", "Targs",
-  "Tindex", "Twhile", "'\\n'", "'^'", "'$'", "Tcount", "Tflat", "'('",
+  "Tindex", "Twhile", "'\\n'", "'^'", "'$'", "Tcount", "Tjoin", "'('",
   "')'", "'{'", "'}'", "';'", "'&'", "'='", "$accept", "rc", "line",
   "body", "paren", "block", "cmds", "cmdsln", "ifbody", "assign", "redir",
   "epilog", "cmd", "basic", "atom", "word", "executable", "nonkeyword",
@@ -1625,9 +1625,9 @@ yyreduce:
 #line 1626 "sys/cmd/rc/parse.c"
     break;
 
-  case 43: /* nonkeyword: Tflat atom  */
+  case 43: /* nonkeyword: Tjoin atom  */
 #line 111 "sys/cmd/rc/syntax.y"
-                  { (yyval.tree) = maketree1(Tflat, (yyvsp[0].tree)); }
+                  { (yyval.tree) = maketree1(Tjoin, (yyvsp[0].tree)); }
 #line 1632 "sys/cmd/rc/parse.c"
     break;
 
diff --git a/sys/cmd/rc/parse.h b/sys/cmd/rc/parse.h
index ef389bc..64d567a 100644
--- a/sys/cmd/rc/parse.h
+++ b/sys/cmd/rc/parse.h
@@ -73,7 +73,7 @@ extern int yydebug;
     Tindex = 274,                  /* Tindex  */
     Twhile = 275,                  /* Twhile  */
     Tcount = 276,                  /* Tcount  */
-    Tflat = 277                    /* Tflat  */
+    Tjoin = 277                    /* Tjoin  */
   };
   typedef enum yytokentype yytoken_kind_t;
 #endif
@@ -101,7 +101,7 @@ extern int yydebug;
 #define Tindex 274
 #define Twhile 275
 #define Tcount 276
-#define Tflat 277
+#define Tjoin 277
 
 /* Value type.  */
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
diff --git a/sys/cmd/rc/syntax.y b/sys/cmd/rc/syntax.y
index 76bcd88..b486484 100644
--- a/sys/cmd/rc/syntax.y
+++ b/sys/cmd/rc/syntax.y
@@ -17,7 +17,7 @@
 %left Tbang Tsubshell
 %left Tpipe;
 %left '^';
-%right '$' Tcount Tflat
+%right '$' Tcount Tjoin
 %left Tindex
 
 /* semantic types */
@@ -108,7 +108,7 @@ nonkeyword:
 | '$' atom        { $$ = maketree1('$', $2); }
 | '(' wordsnl ')' { $$ = $2; }
 | Tcount atom     { $$ = maketree1(Tcount, $2); }
-| Tflat atom      { $$ = maketree1(Tflat, $2); }
+| Tjoin atom      { $$ = maketree1(Tjoin, $2); }
 //| '`'  block      { $$ = maketree1('`', $2); }
 
 keyword: