diff options
Diffstat (limited to 'ps/reader.ps')
| -rw-r--r-- | ps/reader.ps | 60 |
1 files changed, 41 insertions, 19 deletions
diff --git a/ps/reader.ps b/ps/reader.ps index 948bf3b..bdc4580 100644 --- a/ps/reader.ps +++ b/ps/reader.ps @@ -64,8 +64,7 @@ /cnt 0 def { % loop idx str length ge { %if EOF - (unexpected EOF reading string) - throw + (unexpected EOF reading string) _throw } if /ch str idx get def % current character /idx idx 1 add def @@ -110,21 +109,21 @@ % return: atom string new_idx } def -% read_list: read a single list from string/idx -% string idx -> read_list -> list string new_idx -/read_list { - %(in read_list\n) print +% read_until: read a list from string/idx until stopchar is found +% string idx stopchar -> read_until -> list string new_idx +/read_until { + %(in read_until\n) print + /stopchar exch def /idx exch 1 add def /str exch def [ { % loop str idx read_spaces /idx exch def pop str length idx le { %if EOF - (unexpected EOF reading list) - throw + (unexpected EOF reading list) _throw } if /ch str idx get def % current character - ch 41 eq { exit } if % ')' is end of list + ch stopchar eq { exit } if % stop at stopchar str idx read_form /idx exch def pop } loop ] @@ -156,9 +155,21 @@ /idx exch def /str exch def - idx str length ge { exit } if % EOF, break loop + idx str length ge { (unexpected EOF) _throw } if % EOF /ch str idx get def % current character - ch 39 eq { %if '\'' + ch 59 eq { %if ';' + { % loop + /idx idx 1 add def % increment idx + str length idx le { exit } if % EOF, break loop + /ch str idx get def % current character + % if newline then add 1 more idx and exit + ch 10 eq { + /idx idx 1 add def + exit + } if + } loop + str idx read_form % recur to get next form + }{ ch 39 eq { %if '\'' /idx idx 1 add def str idx read_form 3 -1 roll /quote exch 2 _list 3 1 roll @@ -177,21 +188,32 @@ str idx read_form 3 -1 roll /unquote exch 2 _list 3 1 roll } ifelse + }{ ch 94 eq { %if '^' + /idx idx 1 add def + str idx read_form read_form % stack: meta form str idx + 4 2 roll exch /with-meta 3 1 roll 3 _list 3 1 roll + }{ ch 64 eq { %if '@' + /idx idx 1 add def + str idx read_form + 3 -1 roll /deref exch 2 _list 3 1 roll }{ ch 40 eq { %if '(' - str idx read_list + str idx 41 read_until + 3 -1 roll _list_from_array 3 1 roll }{ ch 41 eq { %elseif ')' - (unexpected '\)') throw - }{ ch 91 eq { %elseif '[' - (unexpected '[') throw + (unexpected '\)') _throw + }{ ch 91 eq { %if '(' + str idx 93 read_until + 3 -1 roll _vector_from_array 3 1 roll }{ ch 93 eq { %elseif ']' - (unexpected ']') throw + (unexpected ']') _throw }{ ch 123 eq { %elseif '{' - (unexpected '{') throw + str idx 125 read_until + 3 -1 roll _hash_map_from_array 3 1 roll }{ ch 125 eq { %elseif '}' - (unexpected '}') throw + (unexpected '}') _throw }{ % else str idx read_atom - } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse + } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse % return: ast string new_idx end } def |