From d3de6b0f3fa8d52be6b08a97fe0e63047d780abb Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Sat, 1 Mar 2025 16:14:00 +0100
Subject: [PATCH] Automatic replacement of .param by .func .param xxx1(x,y) =
 '2*x+y'  --->  .func xxx1(x,y) '2*x+y'

---
 src/frontend/inpcom.c | 76 ++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 75 insertions(+), 1 deletion(-)

diff --git a/src/frontend/inpcom.c b/src/frontend/inpcom.c
index c60a16d6c..ac159c829 100644
--- a/src/frontend/inpcom.c
+++ b/src/frontend/inpcom.c
@@ -134,6 +134,7 @@ static void expand_section_references(struct card *deck,
 static void inp_grab_func(struct function_env *, struct card *deck);
 static void inp_fix_inst_calls_for_numparam(
         struct names *subckt_w_params, struct card *deck);
+static void inp_replace_param_by_func(struct card* deck);
 static void inp_expand_macros_in_func(struct function_env *);
 static struct card *inp_expand_macros_in_deck(
         struct function_env *, struct card *deck);
@@ -1124,7 +1125,7 @@ struct card *inp_readall(FILE *fp, const char *dir_name, const char* file_name,
         subckt_params_to_param(working);
 
         rv.line_number = inp_split_multi_param_lines(working, rv.line_number);
-
+        inp_replace_param_by_func(working);
         inp_fix_macro_param_func_paren_io(working);
 
         static char *statfcn[] = {
@@ -5674,6 +5675,12 @@ static int inp_split_multi_param_lines(struct card *card, int line_num)
                 int paren_depth = 0;
 
                 beg_param = skip_back_ws(equal_ptr, curr_line);
+                /* Special treatment if .param is a .func:
+                   move back to opening '(' */
+                if (*(beg_param - 1) == ')') {
+                    while (beg_param > curr_line && *beg_param != '(')
+                        beg_param--;
+                }
                 beg_param = skip_back_non_ws(beg_param, curr_line);
                 end_param = skip_ws(equal_ptr + 1);
                 while (*end_param && !isspace_c(*end_param)) {
@@ -7981,6 +7988,73 @@ static void inp_fix_temper_in_param(struct card *deck)
     inp_delete_funcs(funcs);
 }
 
+/* Convert .param lines containing user defined functions
+ * into .func lines:
+ * .param xxx1(x,y) = '2*x+y'  --->  .func xxx1(x,y) ''2*x+y''
+  */
+
+static void inp_replace_param_by_func(struct card* deck)
+{
+    int skip_control = 0;
+    struct card* card;
+
+    for (card = deck; card; card = card->nextcard) {
+
+        char* curr_line = card->line;
+
+        if (*curr_line == '*')
+            continue;
+
+        /* exclude any command inside .control ... .endc */
+        if (ciprefix(".control", curr_line)) {
+            skip_control++;
+            continue;
+        }
+        else if (ciprefix(".endc", curr_line)) {
+            skip_control--;
+            continue;
+        }
+        else if (skip_control > 0) {
+            continue;
+        }
+
+        if (ciprefix(".para", curr_line)) {
+
+            char *fcn, *equal_ptr, *tmpstr;
+            bool found = FALSE;
+
+            fcn = nexttok(curr_line); // skip .param
+
+            if (!fcn)
+                continue;
+
+            equal_ptr = find_assignment(curr_line);
+
+            if (!equal_ptr)
+                continue;
+
+            tmpstr = equal_ptr;
+            while (tmpstr > curr_line) {
+                tmpstr--;
+                if (*tmpstr == ')') {
+                    found = TRUE;
+                    break;
+                }
+            }
+            if (!found)
+                continue;
+
+            *equal_ptr = ' ';
+            curr_line[0] = ' ';
+            curr_line[1] = '.';
+            curr_line[2] = 'f';
+            curr_line[3] = 'u';
+            curr_line[4] = 'n';
+            curr_line[5] = 'c';
+            fprintf(stdout, "%s\n", curr_line);
+        }
+    }
+}
 
 /* Convert .param lines containing function 'agauss' and others
  *  (function name handed over by *fcn),  into .func lines: