update num->string algorithm, now the to_string will output strings with no tailing zeros

README.md

@@ -811,7 +811,7 @@ Finally i learned `LL(1)` and `LL(k)` and wrote a parser for math formulas in ve
 
 In version 0.17(2019/9/15) 0.18(2019/9/18) 0.19(2019/10/1)i was playing the parser happily and after that i wrote version 1.0.
 
-__This project began at 2019/8/31__.
+__This project began at 2019/7/25__.
 
 ## __Abstract Syntax Tree__
 

nasal_builtin.h

@@ -399,8 +399,11 @@ nasal_ref builtin_str(nasal_ref* local,nasal_gc& gc)
     nasal_ref val=local[1];
     if(val.type!=vm_num)
         return builtin_err("str","\"number\" must be number");
+    std::string tmp=std::to_string(val.num());
+    tmp.erase(tmp.find_last_not_of('0')+1,std::string::npos);
+    tmp.erase(tmp.find_last_not_of('.')+1,std::string::npos);
     nasal_ref ret=gc.alloc(vm_str);
-    *ret.str()=std::to_string(val.num());
+    *ret.str()=tmp;
     return ret;
 }
 nasal_ref builtin_size(nasal_ref* local,nasal_gc& gc)

nasal_gc.h

@@ -312,7 +312,12 @@ std::string nasal_ref::to_string()
     if(type==vm_str)
         return *str();
     else if(type==vm_num)
-        return std::to_string(num());
+    {
+        std::string tmp=std::to_string(num());
+        tmp.erase(tmp.find_last_not_of('0')+1,std::string::npos);
+        tmp.erase(tmp.find_last_not_of('.')+1,std::string::npos);
+        return tmp;
+    }
     return "";
 }
 void nasal_ref::print()

test/ascii-art.nas

@@ -116,15 +116,15 @@ var curve4=func()
 }
 var curve5=func(){
     for(var i=0;i<=9;i+=1)
-        println(i,"\e["~split(".",str(i))[0]~"mh \e[0m");
+        println(i,"\e["~i~"mh \e[0m");
     for(var i=30;i<=37;i+=1)
-        println(i,"\e["~split(".",str(i))[0]~"mh \e[0m");
+        println(i,"\e["~i~"mh \e[0m");
     for(var i=40;i<=47;i+=1)
-        println(i,"\e["~split(".",str(i))[0]~"mh \e[0m");
+        println(i,"\e["~i~"mh \e[0m");
     for(var i=90;i<=97;i+=1)
-        println(i,"\e["~split(".",str(i))[0]~"mh \e[0m");
+        println(i,"\e["~i~"mh \e[0m");
     for(var i=100;i<=107;i+=1)
-        println(i,"\e["~split(".",str(i))[0]~"mh \e[0m");
+        println(i,"\e["~i~"mh \e[0m");
 }
 var curve6=func(){
     var shadow=["m░\e[0m","m▒\e[0m","m▓\e[0m","m█\e[0m","m▀\e[0m","m▄\e[0m","m▐\e[0m","m▌\e[0m"];