✎ soc:2009:lynusvaz:notes:start

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.

====== Lynus Vaz: Enhanced scripting language ======
===== Notes =====
I've taken a few ideas from Fabrice Bellard's C OTCC compiler: http://bellard.org/otcc/

Also looking at [[http://www.gnu.org/software/bash/bash.html|bash]]

Proposed syntax:
  
  LINES           => LINE '\n' LINES | e
  LINE            => WORD | WORD WS ARG_LIST | e
  ARG_LIST        => ARG WS ARG_LIST | e
  ARG             => WORD
  SP              => ' ' | '\t'
  WS              => SP | SP WS
  NOT_EXP         => (any - { SP, '$(', ')', '${', '}')    /* Represents characters not expanded */
  WORD            => NOT_EXP WORD | EXP WORD | NOT_EXP | EXP
  EXP             => EXPR_EXP | VAR_EXP                /* Expansions */
  EXPR_EXP        => '$(' EXPR ')'
  VAR_EXP         => '${' (any - { '}' })+ '}'       
  EXPR            => TERM | TERM BIN_OP EXPR | MONO_OP EXPR
  TERM            => VAR_EXP | STRING
  NUM             => ('+' | '-' )? ( '(' EXPR ')' | (digit)+ )               
  STRING          => (any - { '$(', ')', '${', '}', ' ', BIN_OP, MONO_OP})+    /* This will help with string comparison */
  BIN_OP          => '*' |  '/' | '%'             /* Convert both operands to integers */
                     | '+' | '-'
                     | '<<' |  '>>'
                     | '<' | '<=' | '>' | '>='
                     | '!=' | '=='                          /* Should also work for strings */
                     | '&'
                     | '|'
                     | '^'
                     | '&&'
                     | '||'
  MONO_OP         => '~' | '!'

Trace: • drivers • freedos • bootovernfs • winnt_sanbootconf • dhcp_-_build_instructions • todo • romburning • acknowledgements • httpboot • week4 • week2 • soc • howtos • tracetcpstack • ideas • download • qemu • dnsmasq