...

src/ceval.h

@@ -80,7 +80,6 @@ __NEXT_STEP:;
     TARGET(LOAD_FALSE) PUSH(False); DISPATCH();
     TARGET(LOAD_INTEGER) PUSH(VAR(byte.arg)); DISPATCH();
     TARGET(LOAD_ELLIPSIS) PUSH(Ellipsis); DISPATCH();
-    TARGET(LOAD_BUILTIN_EVAL) PUSH(builtins->attr(m_eval)); DISPATCH();
     TARGET(LOAD_FUNCTION) {
         FuncDecl_ decl = co->func_decls[byte.arg];
         bool is_simple = decl->starred_arg==-1 && decl->kwargs.size()==0 && !decl->code->is_generator;
@@ -547,6 +546,11 @@ __NEXT_STEP:;
     TARGET(SETUP_DOCSTRING)
         TOP()->attr().set(__doc__, co_consts[byte.arg]);
         DISPATCH();
+    TARGET(FORMAT_STRING) {
+        _0 = POPX();
+        const Str& spec = CAST(Str&, co_consts[byte.arg]);
+        PUSH(VAR(format(spec, _0)));
+    } DISPATCH();
 #if !PK_ENABLE_COMPUTED_GOTO
 #if DEBUG_EXTRA_CHECK
     default: throw std::runtime_error(fmt(OP_NAMES[byte.op], " is not implemented"));

src/expr.h

@@ -536,10 +536,19 @@ struct FStringExpr: Expr{
                 ctx->emit(OP_LOAD_CONST, ctx->add_const(VAR(literal)), line);
                 size++;
             }
-            ctx->emit(OP_LOAD_BUILTIN_EVAL, BC_NOARG, line);
-            ctx->emit(OP_LOAD_NULL, BC_NOARG, BC_KEEPLINE);
-            ctx->emit(OP_LOAD_CONST, ctx->add_const(VAR(m[1].str())), line);
-            ctx->emit(OP_CALL, 1, line);
+            Str expr = m[1].str();
+            int conon = expr.index(":");
+            if(conon >= 0){
+                ctx->emit(
+                    OP_LOAD_NAME,
+                    StrName(expr.substr(0, conon)).index,
+                    line
+                );
+                Str spec = expr.substr(conon+1);
+                ctx->emit(OP_FORMAT_STRING, ctx->add_const(VAR(spec)), line);
+            }else{
+                ctx->emit(OP_LOAD_NAME, StrName(expr).index, line);
+            }
             size++;
             i = (int)(m.position() + m.length());
         }

src/opcodes.h

@@ -14,7 +14,6 @@ OPCODE(LOAD_TRUE)
 OPCODE(LOAD_FALSE)
 OPCODE(LOAD_INTEGER)
 OPCODE(LOAD_ELLIPSIS)
-OPCODE(LOAD_BUILTIN_EVAL)
 OPCODE(LOAD_FUNCTION)
 OPCODE(LOAD_NULL)
 /**************************/
@@ -111,4 +110,5 @@ OPCODE(RAISE)
 OPCODE(RE_RAISE)
 /**************************/
 OPCODE(SETUP_DOCSTRING)
+OPCODE(FORMAT_STRING)
 #endif

src/str.h

@@ -164,6 +164,10 @@ struct Str{
         return ret;
     }
 
+    Str substr(int start) const {
+        return substr(start, size - start);
+    }
+
     char* c_str_dup() const {
         char* p = (char*)malloc(size + 1);
         memcpy(p, data, size);
@@ -396,7 +400,6 @@ const StrName __setattr__ = StrName::get("__setattr__");
 const StrName __call__ = StrName::get("__call__");
 const StrName __doc__ = StrName::get("__doc__");
 
-const StrName m_eval = StrName::get("eval");
 const StrName m_self = StrName::get("self");
 const StrName m_dict = StrName::get("dict");
 const StrName m_set = StrName::get("set");

src/vm.h

@@ -395,6 +395,7 @@ public:
     PyObject* getattr(PyObject* obj, StrName name, bool throw_err=true);
     PyObject* get_unbound_method(PyObject* obj, StrName name, PyObject** self, bool throw_err=true, bool fallback=false);
     void parse_int_slice(const Slice& s, int length, int& start, int& stop, int& step);
+    Str format(Str, PyObject*);
     void setattr(PyObject* obj, StrName name, PyObject* value);
     template<int ARGC>
     void bind_method(PyObject*, Str, NativeFuncC);
@@ -641,6 +642,60 @@ inline PyObject* VM::asRepr(PyObject* obj){
     return call_method(obj, __repr__);
 }
 
+inline Str VM::format(Str spec, PyObject* obj){
+    char type = spec.end()[-1];
+    int dot = -1;
+    int width, precision;
+    char align;
+    if(spec[0] == '>'){
+        align = '>';
+        spec = spec.substr(1);
+        dot = spec.index(".");
+    }else if(spec[0] == '<'){
+        align = '<';
+        spec = spec.substr(1);
+        dot = spec.index(".");
+    }else{
+        if(is_int(obj) || is_float(obj)) align = '>';
+        else align = '<';
+    }
+
+    try{
+        if(dot >= 0){
+            width = Number::stoi(spec.substr(0, dot).str());
+            precision = Number::stoi(spec.substr(dot+1).str());
+        }else{
+            width = Number::stoi(spec.str());
+            precision = -1;
+        }
+    }catch(...){
+        ValueError("invalid format specifer");
+    }
+
+    if(type != 'f' && dot >= 0) ValueError("precision not allowed in the format specifier");
+    Str ret;
+    if(type == 'f'){
+        f64 val = num_to_float(obj);
+        if(precision < 0) precision = 6;
+        std::stringstream ss;
+        ss << std::fixed << std::setprecision(precision) << val;
+        ret = ss.str();
+    }else if(type == 'd'){
+        ret = std::to_string(CAST(i64, obj));
+    }else if(type == 's'){
+        ret = CAST(Str&, obj);
+    }else{
+        ret = CAST(Str&, asStr(obj));
+    }
+    if(width > ret.length()){
+        int pad = width - ret.length();
+        std::string padding(pad, ' ');
+        if(align == '>') ret = padding.c_str() + ret;
+        else ret = ret + padding.c_str();
+    }
+    return ret;
+}
+
 inline PyObject* VM::new_module(StrName name) {
     PyObject* obj = heap._new<DummyModule>(tp_module, DummyModule());
     obj->attr().set(__name__, VAR(name.sv()));

tests/25_rawstring.py

@@ -17,12 +17,29 @@ asds1321321321测试\测试'''
 
 assert s == 'asdasd\nasds1321321321测试\\测试'
 
-assert f'123{2*2}56789' == '123456789'
+t = 4
+assert f'123{t}56789' == '123456789'
 
+b = 123
 s = f'''->->{s}<-<-
-{123}
+{b}
 '''
 
 assert s == '->->asdasd\nasds1321321321测试\\测试<-<-\n123\n'
 
-assert r''' ' ''' == " ' "
+assert r''' ' ''' == " ' "
+
+a = 10
+assert f'{a}' == '10'
+assert f'{a:>10}' == '        10'
+assert f'{a:<10}' == '10        '
+assert f'{a:<10.2f}' == '10.00     '
+assert f'{a:>10.2f}' == '     10.00'
+assert f'{a:3d}' == ' 10'
+assert f'{a:10d}' == '        10'
+assert f'{a:1d}' == '10'
+b = '123'
+assert f'{b:10}' == '123       '
+assert f'{b:>10}' == '       123'
+assert f'{b:1}' == '123'
+assert f'{b:10s}' == '123       '