Clarify some or exclusive expressions

Since relational expresions are always evaluated to 0 or 1, we can use
bitwise xor operator instead of using more complex boolean expressions.
---
 st.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/st.c b/st.c
index 67fa790..9864442 100644 (file)
--- a/st.c
+++ b/st.c
@@ -1475,15 +1475,15 @@ tsetmode(bool priv, bool set, int *args, int narg) {
                                break;
                        case 1049: /* = 1047 and 1048 */
                        case 47:
-                       case 1047:
-                               if(IS_SET(MODE_ALTSCREEN))
+                       case 1047: {
+                               bool alt = IS_SET(MODE_ALTSCREEN) != 0;
+                               if(alt)
                                        tclearregion(0, 0, term.col-1, term.row-1);
-                               if((set && !IS_SET(MODE_ALTSCREEN)) ||
-                                               (!set && IS_SET(MODE_ALTSCREEN))) {
+                               if(set ^ alt)           /* set is always 1 or 0 */
                                        tswapscreen();
-                               }
                                if(*args != 1049)
                                        break;
+                       }
                                /* pass through */
                        case 1048:
                                tcursor((set) ? CURSOR_SAVE : CURSOR_LOAD);
@@ -2546,9 +2546,9 @@ drawregion(int x1, int y1, int x2, int y2) {
        int ic, ib, x, y, ox, sl;
        Glyph base, new;
        char buf[DRAW_BUF_SIZ];
-       bool ena_sel = sel.bx != -1, alt = IS_SET(MODE_ALTSCREEN);
+       bool ena_sel = sel.bx != -1, alt = IS_SET(MODE_ALTSCREEN) != 0;
 
-       if((sel.alt && !alt) || (!sel.alt && alt))
+       if((sel.alt != 0) ^ alt)
                ena_sel = 0;
        if(!(xw.state & WIN_VISIBLE))
                return;