diff --git a/extlib/benz/codegen.c b/extlib/benz/codegen.c
index 7b2adb46..eab53fd0 100644
--- a/extlib/benz/codegen.c
+++ b/extlib/benz/codegen.c
@@ -37,7 +37,7 @@ typedef struct analyze_state {
   pic_state *pic;
   analyze_scope *scope;
   pic_sym rCONS, rCAR, rCDR, rNILP;
-  pic_sym rSYMBOL_P, rPAIR_P;
+  pic_sym rSYMBOLP, rPAIRP;
   pic_sym rADD, rSUB, rMUL, rDIV;
   pic_sym rEQ, rLT, rLE, rGT, rGE, rNOT;
   pic_sym rVALUES, rCALL_WITH_VALUES;
@@ -76,8 +76,8 @@ new_analyze_state(pic_state *pic)
   register_renamed_symbol(pic, state, rCAR, pic->PICRIN_BASE, "car");
   register_renamed_symbol(pic, state, rCDR, pic->PICRIN_BASE, "cdr");
   register_renamed_symbol(pic, state, rNILP, pic->PICRIN_BASE, "null?");
-  register_renamed_symbol(pic, state, rSYMBOL_P, pic->PICRIN_BASE, "symbol?");
-  register_renamed_symbol(pic, state, rPAIR_P, pic->PICRIN_BASE, "pair?");
+  register_renamed_symbol(pic, state, rSYMBOLP, pic->PICRIN_BASE, "symbol?");
+  register_renamed_symbol(pic, state, rPAIRP, pic->PICRIN_BASE, "pair?");
   register_renamed_symbol(pic, state, rADD, pic->PICRIN_BASE, "+");
   register_renamed_symbol(pic, state, rSUB, pic->PICRIN_BASE, "-");
   register_renamed_symbol(pic, state, rMUL, pic->PICRIN_BASE, "*");
@@ -792,13 +792,13 @@ analyze_node(analyze_state *state, pic_value obj, bool tailpos)
 	ARGC_ASSERT(1);
         return CONSTRUCT_OP1(pic->sNILP);
       }
-      else if (sym == state->rSYMBOL_P) {
+      else if (sym == state->rSYMBOLP) {
         ARGC_ASSERT(1);
-        return CONSTRUCT_OP1(pic->sSYMBOL_P);
+        return CONSTRUCT_OP1(pic->sSYMBOLP);
       }
-      else if (sym == state->rPAIR_P) {
+      else if (sym == state->rPAIRP) {
         ARGC_ASSERT(1);
-        return CONSTRUCT_OP1(pic->sPAIR_P);
+        return CONSTRUCT_OP1(pic->sPAIRP);
       }
       else if (sym == state->rADD) {
         return analyze_add(state, obj, tailpos);
@@ -1340,15 +1340,15 @@ codegen(codegen_state *state, pic_value obj)
     cxt->clen++;
     return;
   }
-  else if (sym == pic->sSYMBOL_P) {
+  else if (sym == pic->sSYMBOLP) {
     codegen(state, pic_list_ref(pic, obj, 1));
-    cxt->code[cxt->clen].insn = OP_SYMBOL_P;
+    cxt->code[cxt->clen].insn = OP_SYMBOLP;
     cxt->clen++;
     return;
   }
-  else if (sym == pic->sPAIR_P) {
+  else if (sym == pic->sPAIRP) {
     codegen(state, pic_list_ref(pic, obj, 1));
-    cxt->code[cxt->clen].insn = OP_PAIR_P;
+    cxt->code[cxt->clen].insn = OP_PAIRP;
     cxt->clen++;
     return;
   }
diff --git a/extlib/benz/gc.c b/extlib/benz/gc.c
index c82d6838..9c89682e 100644
--- a/extlib/benz/gc.c
+++ b/extlib/benz/gc.c
@@ -535,7 +535,7 @@ gc_mark_global_symbols(pic_state *pic)
   M(sCOND_EXPAND); M(sAND); M(sOR); M(sELSE); M(sLIBRARY);
   M(sONLY); M(sRENAME); M(sPREFIX); M(sEXCEPT);
   M(sCONS); M(sCAR); M(sCDR); M(sNILP);
-  M(sSYMBOL_P); M(sPAIR_P);
+  M(sSYMBOLP); M(sPAIRP);
   M(sADD); M(sSUB); M(sMUL); M(sDIV); M(sMINUS);
   M(sEQ); M(sLT); M(sLE); M(sGT); M(sGE); M(sNOT);
   M(sREAD); M(sFILE);
diff --git a/extlib/benz/include/picrin.h b/extlib/benz/include/picrin.h
index 5bbbf620..a0a87575 100644
--- a/extlib/benz/include/picrin.h
+++ b/extlib/benz/include/picrin.h
@@ -96,7 +96,7 @@ typedef struct {
   pic_sym sCOND_EXPAND, sAND, sOR, sELSE, sLIBRARY;
   pic_sym sONLY, sRENAME, sPREFIX, sEXCEPT;
   pic_sym sCONS, sCAR, sCDR, sNILP;
-  pic_sym sSYMBOL_P, sPAIR_P;
+  pic_sym sSYMBOLP, sPAIRP;
   pic_sym sADD, sSUB, sMUL, sDIV, sMINUS;
   pic_sym sEQ, sLT, sLE, sGT, sGE, sNOT;
   pic_sym sREAD, sFILE;
diff --git a/extlib/benz/include/picrin/irep.h b/extlib/benz/include/picrin/irep.h
index 70597a71..80159547 100644
--- a/extlib/benz/include/picrin/irep.h
+++ b/extlib/benz/include/picrin/irep.h
@@ -35,8 +35,8 @@ enum pic_opcode {
   OP_CAR,
   OP_CDR,
   OP_NILP,
-  OP_SYMBOL_P,
-  OP_PAIR_P,
+  OP_SYMBOLP,
+  OP_PAIRP,
   OP_ADD,
   OP_SUB,
   OP_MUL,
@@ -152,11 +152,11 @@ pic_dump_code(pic_code c)
   case OP_NILP:
     puts("OP_NILP");
     break;
-  case OP_SYMBOL_P:
-    puts("OP_SYMBOL_P");
+  case OP_SYMBOLP:
+    puts("OP_SYMBOLP");
     break;
-  case OP_PAIR_P:
-    puts("OP_PAIR_P");
+  case OP_PAIRP:
+    puts("OP_PAIRP");
     break;
   case OP_CDR:
     puts("OP_CDR");
diff --git a/extlib/benz/state.c b/extlib/benz/state.c
index 43a44934..a69c2331 100644
--- a/extlib/benz/state.c
+++ b/extlib/benz/state.c
@@ -117,8 +117,8 @@ pic_open(int argc, char *argv[], char **envp)
   S(sCAR, "car");
   S(sCDR, "cdr");
   S(sNILP, "null?");
-  S(sSYMBOL_P, "symbol?");
-  S(sPAIR_P, "pair?");
+  S(sSYMBOLP, "symbol?");
+  S(sPAIRP, "pair?");
   S(sADD, "+");
   S(sSUB, "-");
   S(sMUL, "*");
diff --git a/extlib/benz/vm.c b/extlib/benz/vm.c
index 7bbaaf24..cc0aa9b7 100644
--- a/extlib/benz/vm.c
+++ b/extlib/benz/vm.c
@@ -706,7 +706,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, pic_value args)
     &&L_OP_GREF, &&L_OP_GSET, &&L_OP_LREF, &&L_OP_LSET, &&L_OP_CREF, &&L_OP_CSET,
     &&L_OP_JMP, &&L_OP_JMPIF, &&L_OP_NOT, &&L_OP_CALL, &&L_OP_TAILCALL, &&L_OP_RET,
     &&L_OP_LAMBDA, &&L_OP_CONS, &&L_OP_CAR, &&L_OP_CDR, &&L_OP_NILP,
-    &&L_OP_SYMBOL_P, &&L_OP_PAIR_P,
+    &&L_OP_SYMBOLP, &&L_OP_PAIRP,
     &&L_OP_ADD, &&L_OP_SUB, &&L_OP_MUL, &&L_OP_DIV, &&L_OP_MINUS,
     &&L_OP_EQ, &&L_OP_LT, &&L_OP_LE, &&L_OP_STOP
   };
@@ -1046,14 +1046,14 @@ pic_apply(pic_state *pic, struct pic_proc *proc, pic_value args)
       NEXT;
     }
 
-    CASE(OP_SYMBOL_P) {
+    CASE(OP_SYMBOLP) {
       pic_value p;
       p = POP();
       PUSH(pic_bool_value(pic_sym_p(p)));
       NEXT;
     }
 
-    CASE(OP_PAIR_P) {
+    CASE(OP_PAIRP) {
       pic_value p;
       p = POP();
       PUSH(pic_bool_value(pic_pair_p(p)));