add | operator between expressions; project euler #6

diff --git a/src/compile/ir.c b/src/compile/ir.c
index 3e214be..5ab9b6c 100644 (file)
--- a/src/compile/ir.c
+++ b/src/compile/ir.c
@@ -17,6 +17,7 @@ typedef struct varmapentry {
 static sbIrChunk *compile_ast_function(hIrProgram ir, sbAst params, sbAst seqast);
 static sbIrChunk *new_chunk(hIrProgram ir);
 static void chunk_deinitialize(hIrChunk ck);
+static sbIrVariable *create_var(hIrChunk ck, const char *name, usize name_len);
 
 void sbIrProgram_initialize(hIrProgram ir, usize initial_arena_size) {
   *ir = (sbIrProgram) {0};
@@ -107,6 +108,14 @@ static void chunk_deinitialize(hIrChunk ck) {
   sbBuffer_deinitialize(&ck->closed_vars);
 }
 
+static sbIrVariable *var_at_index(hIrChunk ck, usize index) {
+  if (ck->program->varmapping.size / sizeof(varmapentry) > index) {
+    return BUFFER_INDEX(ck->program->varmapping, varmapentry, index).var;
+  } else {
+    return NO_VAR;
+  }
+}
+
 /* find variables that already exist */
 static sbIrVariable *existing_var(hIrChunk ck, const char *name, usize name_len, usize *index_out) {
   usize index = 0;
@@ -187,8 +196,26 @@ static sbIrVariable *bind_upvalue(hIrChunk ck, usize variable_index) {
   }
 }
 
+/* ensure a pipe variable slot is available */
+static sbIrVariable *pipe_var(hIrChunk ck) {
+  if (ck->pipe_var_id == -1) {
+    sbIrVariable *new_pipe_var = create_var(ck, "", 0);
+    ck->pipe_var_id = new_pipe_var->slot_id;
+    new_pipe_var->introduced = BY_IMPLICIT;
+    return new_pipe_var;
+  } else {
+    return var_at_index(ck, ck->pipe_var_id + ck->lowest_var_id);
+  }
+}
+
 /* to look up a variable name in source code */
 static sbIrVariable *var_name(hIrChunk ck, const char *name, usize name_len) {
+  if (name_len == 1 && name[0] == '_') {
+    /* _ variable is resolved specially depending on context... currently, this is
+     * just for the pipe variable */
+    return pipe_var(ck);
+  }
+
   usize index;
   sbIrVariable *v = existing_var(ck, name, name_len, &index);
 
@@ -206,11 +233,16 @@ static sbIrVariable *var_name(hIrChunk ck, const char *name, usize name_len) {
 
 /* we can introduce new variables into a scope using LET */
 static sbIrVariable *create_var(hIrChunk ck, const char *name, usize name_len) {
-  sbIrVariable *already_existing = existing_var(ck, name, name_len, NULL);
-  if (already_existing != NO_VAR) {
-    // TODO this should probably just be a warning
-    chunk_error(ck, "redeclaration of variable '%s'!\n", name);
-    return NO_VAR;
+  /* we can pass an empty name to create extra 'internal' variables that don't
+   * have real names, as part of a sort of desugar thing. but you have to remember
+   * their ID numbers */
+  if (name_len > 0) {
+    sbIrVariable *already_existing = existing_var(ck, name, name_len, NULL);
+    if (already_existing != NO_VAR) {
+      // TODO this should probably just be a warning
+      chunk_error(ck, "redeclaration of variable '%s'!\n", name);
+      return NO_VAR;
+    }
   }
 
   sbIrVariable *new_var = sbArena_alloc(&ck->program->arena, sizeof(sbIrVariable));
@@ -527,6 +559,9 @@ static sbIrChunk *compile_ast_function(hIrProgram ir, sbAst paramsAst, sbAst seq
   /* create new scope to hold function parameters */
   usize parameter_scope_level = ck->program->varmapping.size / sizeof(varmapentry);
 
+  /* we have no pipe var right now */
+  ck->pipe_var_id = -1;
+
   /* compile parameters */
   sbIrBindList *arg_binding = compile_ast_bind_list(ck, paramsAst, TRUE, BY_PARAM);
   if (arg_binding) {
@@ -994,6 +1029,12 @@ static sbIrExpr *compile_ast_expr(hIrChunk ck, sbAst node, flag list_context) {
       } else {
         return expr_op(ck, AST_OP_SPLAT, compile_ast_expr(ck, node->op.left, FALSE), NULL);
       }
+    } else if (node->op.type == AST_OP_PIPE) {
+      /* assign LHS to our temporary secret pipe variable,
+       * then use RHS as our value */
+      sbIrExpr *left = compile_ast_expr(ck, node->op.left, FALSE);
+      put_assign(ck, pipe_var(ck), left);
+      return compile_ast_expr(ck, node->op.right, FALSE);
     } else {
       sbIrExpr *left = NULL, *right = NULL;
       if (node->op.left != NO_NODE) {

diff --git a/src/compile/ir.h b/src/compile/ir.h
index a27b2a1..d1a378c 100644 (file)
--- a/src/compile/ir.h
+++ b/src/compile/ir.h
@@ -58,6 +58,7 @@ typedef enum sbIrNameIntroduceType {
   BY_LET,
   BY_PARAM,
   BY_CONTEXT,
+  BY_IMPLICIT,
 } sbIrNameIntroduceType;
 
 typedef struct sbIrLabel {
@@ -144,10 +145,10 @@ typedef struct sbIrChunk {
   i32 id;
   i16 num_args;
   i16 num_upvalues;
-  flag variadic;
   i32 label_count;
   i32 variable_count;
   i32 lowest_var_id;
+  i32 pipe_var_id;
   sbBuffer closed_vars;
   sbBuffer stmts;
 } sbIrChunk;

diff --git a/src/compile/print_ir.c b/src/compile/print_ir.c
index a6102fa..096cbd9 100644 (file)
--- a/src/compile/print_ir.c
+++ b/src/compile/print_ir.c
@@ -1,5 +1,7 @@
 #include "compile/ir.h"
 
+#include "data/symbol.h"
+
 static void print_stmt(sbIrStmt *s);
 
 void sbIrProgram_print(hIrProgram ir) {
@@ -50,14 +52,17 @@ static void print_expr(sbIrExpr *e) {
           print_var(*var);
           debug(", ");
         }
+        debug("\b\b");
       }
-      debug("}");
+      debug(" }");
       break;
     case IR_E_VALUE:
       if (e->value.type == IT_NIL) {
         debug("nil");
       } else if (e->value.type == IT_INTEGER) {
         debug("%lld", (long long)e->value.integer);
+      } else if (e->value.type == IT_SYMBOL) {
+        debug(":%s", sbSymbol_name(e->value.symbol));
       } else {
         debug("some value");
       }
@@ -88,13 +93,18 @@ static void print_expr(sbIrExpr *e) {
       debug(" )");
       break;
     case IR_E_LIST:
-      if (e->list.this) {
-        print_expr(e->list.this);
-      }
       if (e->list.next) {
-        debug(", ");
         print_expr(e->list.next);
+        if (e->list.next->list.next) {
+          debug(", ");
+        }
       }
+      if (e->list.this) {
+        print_expr(e->list.this);
+      }
+      break;
+    case IR_E_CONTEXT:
+      debug("(context var %s)", sbSymbol_name(e->symbol));
       break;
     default:
       debug("something %d", e->type);
@@ -143,7 +153,7 @@ static void print_stmt(sbIrStmt *s) {
       if (s->expr) {
         print_expr(s->expr);
       } else {
-        debug("NOTHING");
+        debug("NOTHING!! (PROBABLY A BUG)");
       }
       debug("\n");
       break;