update docs

femto.tal

@@ -177,11 +177,7 @@
 ( using error! will print the given message before causing )
 ( the interpreter to halt. )
 @error! ( msg* -> )
-    emit-! sp
+    emit-! sp ;print JSR2 nl dbg BRK
-    ;print JSR2
-(    &loop LDAk #00 EQU ,&done JCN
-    LDAk emit INC2 ,&loop JMP
-    &done POP2 ) nl dbg BRK
 
 ( open the given file at editor start up )
 ( )
@@ -713,8 +709,6 @@
     ;redraw-prompt-and-cursor JSR2
     ;return JMP2
 
-( TODO: need to add \r back in for windows )
-
 ( save the file with the filename found in tmp/data )
 @do-save ( -> )
     .buffer/limit LDZ2 ;data SUB2 STH2 ( [size] )
@@ -1566,6 +1560,7 @@
             &term-size-parse-error "Error 20 "parsing 20 "term 20 "size 00
           ]
 
+( perform the undo action )
 @undo ( -> )
     #01 .state/in-undo STZ
     ;undo-stack/pos LDA2 ;undo-stack/data EQU2 ,&noop JCN
@@ -1583,6 +1578,7 @@
     &delete POP ;delete JMP2
     &noop BRK
 
+( free up space in the undo stack by evicting the oldest entry )
 @u-free ( -> )
     ;undo-stack/data STH2k #0003 ADD2 ( st+3 [st] )
     &loop LDAk STH2kr STA
@@ -1591,6 +1587,7 @@
     &done ;undo-stack/pos LDA2k #0003 SUB2 SWP2 STA2
           POP2 POP2r JMP2r
 
+( push a new item on the undo stack )
 @u-push ( c^ addr* -> )
     ;undo-stack/pos DUP2 LDA2 ( c^ addr* top* pos* )
     GTH2 ( c^ addr* top>pos^ ) ,&has-room JCN ( c^ addr* )
@@ -1613,8 +1610,7 @@
 (  - 1 byte: character to insert, or \0 to delete )
 ( )
 ( pos points to the next open stack frame. )
-( )
+( when pos points to data the stack is empty. )
-( when pos points to data the stack is empty, and )
 ( when pos points to pos the stack is full. )
 @undo-stack [
     &data $180 ( 128 steps )

femto.txt

@@ -6,7 +6,7 @@ draws graphics using ANSI control sequences.
 
 this means the terminal must be in raw mode with echo
 turned off. the `femto` wrapper script achieves this
-using `sttry raw -echo` (it also restores the previous
+using `stty raw -echo` (it also restores the previous
 terminal settings on exit).
 
 ---- WARNING ----
@@ -18,15 +18,14 @@ it has bugs!
 please consider making backups (or using version control)
 before femto this to modify important files.
 
-(i'm in the midst of adding regex search so the code
-is particularly untidy right now. sorry!)
-
 ---- getting started ----
 
 you must provide a path to a file when starting femto:
 
     ./femto femto.tal
 
+(if the file does not exist, femto will create it on save.)
+
 the femto launcher script makes many assumptions:
 
  - uxnasm and uxncli are both in the PATH
@@ -39,10 +38,9 @@ packaging process can be explored.
 
 ---- current status ----
 
- - can't create new files that don't already exist
  - can't create new directories while saving
  - doesn't support horizontal scrolling for long lines
- - no search (or search&replace)
+ - no search & replace
  - no copy/paste
  - few help messages
  - doesn't support function keys, mouse, etc.
@@ -56,6 +54,7 @@ the femto status line contains a lot of information:
  3. the number of bytes/lines (e.g. "[49 bytes, 8 lines]"
  4. the x/y cursor position (e.g. "(1,8)" for col 1, row 8)
  5. whether tabs ("[t]") or spaces ("[s]") are inserted by tab key
+ 6. how many items are in the undo stack (e.g. "u:13")
 
 ---- special key bindings ----
 
@@ -65,6 +64,8 @@ the femto status line contains a lot of information:
 
  C-b   move back one character (or LEFT ARROW)
  C-f   move forward one character (or RIGHT ARROW)
+ M-b   move back by one word
+ M-f   move forward by one word
  C-n   move down one line (or DOWN ARROW)
  C-p   move up one line (or UP ARROW)
  M-v   page up (or PAGE DOWN)
@@ -77,10 +78,26 @@ the femto status line contains a lot of information:
  M-g   go to line
  C-l   center screen on cursor line
 
+ C-s   search for a substring [1]
+ M-s   search for matches using a regular expression [1]
+
  C-d   delete
  M-c   toggle color scheme
  M-t   toggle tabs-vs-spaces indentation
- C-l   refresh screen (DEBUG)
 
     (C stands for Control)
     (M stands for Meta, often Alt or Option)
+
+---- search [1] ----
+
+when searching femto will highlight matches and accepts
+the following commands:
+
+ - C-g: cancel the search and restore the cursor
+ - Enter: end the search, leaving the cursor where it is
+ - n (or C-s): move forward to the next match, if any
+ - p (or C-r): move backwards to the previous match, if any
+
+basic regular expression syntax is mostly working, although there
+are notable absences such as character classes (e.g. [] and [^]),
+references to capture groups (e.g. \1), and repetitions (e.g. {n}).