## ml
is a small lisp interpreter based on Adam McDaniel's wisp interpreter (https://github.com/adam-mcdaniel/wisp). It's main purpose is to learn something about more recent c++ 


### Example of use
```
cat <<EOT > /tmp/qs.lsp
(defun qs (l)
    (if (<= (len l) 1)
        l
        (do
            (define pivot (first l))
            (+
                (qs (filter (lambda (n) (> pivot n)) l))
                (list pivot)
                (qs (tail (filter (lambda (n) (<= pivot n)) l)))
            ))
    ))

(print (qs '(10 9 8 7 6 5 4 3 2 10)))
EOT

ml -f /tmp/qs.lsp
```
#### Interactive mode
```
ml
```

#### Documentation
see /doc/Doc.md

#### Compile
```
mkdir -p build
gcc -std=c99 -c -O2 -o linenoise.o clib/linenoise.c
c++ -c -O2  -I/usr/local/opt/openssl/include -Iclib --std=c++17  ml.cpp ml_io.cpp ml_date.cpp ml_string.cpp ml_util.cpp ml_profiler.cpp clib/json11.cpp clib/csvparser.cpp clib/sslclient.cpp clib/printf.cpp clib/linenoise.c usql/exception.cpp usql/lexer.cpp usql/parser.cpp usql/usql.cpp usql/table.cpp usql/table.h usql/row.cpp usql/csvreader.cpp usql/settings.cpp usql/usql.cpp

// on linux c++ -o build/ml -O2 -L/usr/local/lib -L/usr/local/opt/openssl/lib -lm -lstdc++ -lcrypto -lssl *.o
c++ -o build/ml -O2 -L/usr/local/lib -L/usr/local/opt/openssl/lib -lm -lstdc++ -lcrypto -lssl -Wl,-stack_size -Wl,0x1000000 *.o
```
// or cmake

#### Install
```
cp build/ml /usr/local/bin/ml
cp stdlib/*.lsp /usr/local/var/mlisp/
```
or
```
utils/local_install.sh
```


### KNOWNN BUGS
(read-url "https://api.nasdaq.com/api/calendar/dividends/") ; hangs in sslclient.cpp line 132

### TODO
- add debug support, at least call stack
- multiline editing (see kilocpp editor)
- execute system command should capture stderr
- add some mem stats to benchmark
- add tests for usql

#### Code
- add documentation
- rename constants in ml_profiler.h
- replace to_string macro in ml.cpp
- add instrumentation (time, nr of evals, num of atoms, debug info, debug environment etc)

#### Language
- support for "t" symbol as a true 
- support for exceptions
- string functions
    - compare - needed for sorting, cmp ignore case
    - regexp match, regexp tokens    
- date support
  - decode-universal-time (http://www.lispworks.com/documentation/HyperSpec/Body/f_dec_un.htm)
- env functions 
  - get-env, set-env; set-env cannot be implemented in stdlib.lsp, because popen is in fact subshell
- add include-stdlib function for other libs in stdlib dir (during startup stdlib.lsp is loaded only)
- syntax highlighting do VS Code

#### Performance
- define is one of most frequent callee, when in scope with very few vars, lookup sequentially
- first, second are often called -> implement in c++
- push_back - repeatedly without reserving size
- range - with for(int i...) and reserving result size can be 3times faster on (range 1 10000)
- mini_sprintf - unnecesary copying between vector and list
- (do, scope ..) repeatedly assign to acc


### Links
https://github.com/adam-mcdaniel/wisp  
https://github.com/dropbox/json11  
https://github.com/antirez/linenoise


#### read stdout and stderr from popen
https://stackoverflow.com/questions/478898how-do-i-execute-a-command-and-get-the-output-of-the-command-within-c-using-po