+#define if_exists(A,B,C) for_search(A,B,C) break; if(A)
+#define if_args if(argc>1)
+#define switch_for_args for_args switch_str(this_arg)
+#define switch_str(STR) _NEW(S,STR)
+#define if_case(VAL) if(eq(argv[_I],VAL))
+#define for_fields(FIELD,STR) for_valid_split(FIELD,STR,OFS)
+#define for_split_str(A,B,C) for(prefix(A,B,C);A;(A!=B)&&prefix(A,B,C)||(A=NULL))
+#define for_valid_split(A,B,C) for_split_str(A,B,C) if(*A)
+#define switch_for_columns(A,B,C) _FOR_COLUMNS(A,B,C) switch(__I)
+#define switch_for_valid_columns(A,B,C) _FOR_VALID_COLUMNS(A,B,C) switch (_I)
+#define if_column_number(A,B,C,V) _FOR_COLUMNS(A,B,C) if(_I==V)
+#define if_valid_column_number(A,B,C,V) _FOR_VALID_COLUMNS(A,B,C) if(_I==V)