
metaa II

metaa II sankalak likhane key liye ack domen-vishisht prograaming bhasha haye. ise yuu. see. ell. aeye. mein davie vail score dwara 1963-1964 mein banaaya gayaa thaa. metaa II usa shabd kaa upayog kartaa haye jise score vaakya rachana sameekaran kahate hain. isake sanchaalan koo saralata seey iss prakaar samajhaaya gayaa haih
 pratyek "vaakya rachana sameekaran" kaa anuvaad ack punaraavarti upa-rutein mein kiya jaataa haye joe ack vishesh vakyansh sanrachana key liye input string kaa pareekshan kartaa haye, aur paae jaane parr ise hataa detaa haye.
metaa II programon koo ack vyakhya kii gaee bite code bhasha mein sankalit kiya jaataa haye. isaki kshamataon koo darshaane vaale walgol aur smalgol sankalak metaa II bhasha mein likhe gaye they, walgol ack saral beejganitiya bhasha haye jise metaa II koo chitrit karane key uddeshya seey design kiya gayaa haye. smalgol algol 60 kaa kaafee badaa upasamuchchay thaa.
sanketan.
metaa II koo pahali baar metaa I mein likhaa gayaa thaa, joe metaa II kaa ack haath seey sankalit sanskaran haye. itihas spasht naheen haye kii kyaa metaa I metaa II kaa poorna karyanvayan thaa yaa poorna metaa II sankalak koo sankalit karane key liye aavashyak metaa II bhasha kaa aavashyak subset thaa.
apane pralekhan mein, metaa II koo bnf key samaan bataaya gayaa haye, jise aaj ack utpaadan vyaakaran key roop mein samajhaaya gayaa haye. metaa II ack vishleshanatmak vyaakaran haye. vriksh-metaa dastaavez mein inn bhaashaon koo hraskari vyaakaran key roop mein varnit kiya gayaa thaa.
udaaharan key liye, bee. aine. aff. mein, ack ankganitiya abhivyakti koo iss prakaar paribhaashit kiya jaa sakata haih
<aiks. pee. aar.>: = <term> . <expr> <addop> <shabd>
bee. aine. aff. niyam aaj utpaadan niyam hain joe bataate hain kii kaise ghatak bhaagon koo kewal vaidh bhasha nirmaan banaane key liye ikattha kiya jaa sakata haye. ack parcer bhasha koo alag karke isake vipareet kartaa haye. metaa II ack stack-adharit karyatmak parcer prograaming bhasha haye jisamen output nirdesh shamil hain. metaa II mein, pareekshan kaa crum sameekaran dwara nirdisht kiya jaataa haye. anya prograaming bhaashaon kii tarah metaa II bhee apane dher koo baaen punaravritti kaa prayaas karate hue overflo curr dega. metaa II ack $(shoonya yaa adhik) anukram prachaalak kaa upayog kartaa haye. metaa II mein likhaa gayaa aiks. pee. aar. parcing sameekaran ack sashart abhivyakti haye jiska mulyankan baaen seey daaen kiya jaataa haih
expir = pada
 $('+' shabd.baahar ('jodein')
 / '-' shabd.baahar ('upa'));
aiks. pee. aar. sameekaran key oopar '=' kii daaeen or kii abhivyakti dwara paribhaashit kiya jaataa haye. =' seey baaen seey daaen kaa mulyankan karna, shabd pahali cheej haye jiska pareekshan kiya jaanaa chaahiye. yadi karyakal viphalata lautaata haye tou expir whiffle hoe jaataa haye. yadi ack shabd safal hotaa haye tou humm anishchitkaal key liye shoonya yaa usase adhik loop mein pravesh karate hain, aggar humm pahale '+' key liye pareekshan karate hain, yadi vaha whiffle hoe jaataa haye tou vikalp '-' kaa prayaas kiya jaataa haye aur anta mein yadi '-' koo maanyata naheen dee jaati haye tou loop ack hii shabd koo maanyata dene key baad safalata key saath samaapt hoe jaataa haye. yadi ack '+' yaa '-' safal hotaa haye tou shabd kahaa jaayega. aur yadi safal hotaa haye tou loop dohraya jaayega. nested grouping kaa upayog karke bhee expir sameekaran koo vyakt kiya jaa sakata haih
aiks. pee. aar. = pada $(('+'/'-') pada);
udaaharan koo saral banaane key liye code utpaadan tatvon koo chhod diyaa gayaa thaa. praarambhik computers key seemit varna samooh key kaaran varna cocksey _ 1 kaa upayog vikalp, yaa, prachaalak key roop mein kiya gayaa thaa. loop operator, cocksey _ 2 kaa upayog shoonya yaa kissy cheez seey adhik kaa milan karane key liye kiya jaataa haih
aiks. pee. aar. = pada $('+' pada.baahar ('jodein')
 / '-' shabd.baahar ('upa') 
uparokt koo angreji mein vyakt kiya jaa sakata haih ack expir ack aisaa shabd haye jisake baad shoonya yaa usase adhik (plus term yaa minus term) hotaa haye. score ise dakshata mein sahaayata key roop mein varnit kartaa haye, lekin ack saral punaraavarti avrohan sankalak key vipareet yeh yeh bhee sunishchit karega kii ankganitiya sanchaalan kii sahakriyashilta sahee haih
aiks. pee. aar. = pada $('+' pada.baahar ('jodein') 
 / '-' shabd.baahar ('upa')
pada = kaarak $('*' kaarak.baahar ('aim. pee. aaee.')
 / '/' kaarak.baahar ('dive')
kaarak = (.ids
 /.sankhya
 / '(' expir ')')
 ('^' kaarak.baahar ('exp')
 /.khaali);
ack loop yaa sahee ("poonchh") punaravritti key saath ack anukram koo vyakt karane kii kshamata key saath, mulyankan key crum koo niyantrit kiya jaa sakata haye.
vakyavinyas key niyam ghoshanaatmak prateet hotey hain, lekin vaastav mein unake shabdarth vinirdeshon dwara anivarya curr diye jaate hain.
operation.
metaa II ack stack machine key liye assembly code kaa output detaa haye. iska mulyankan karna aar. pee. aine. calculator kaa upayog karane key samaan haye. 
expir = pada
 $('+' shabd.baahar ('jodein')
 / '-' shabd.baahar ('upa'));
pada = kaarak
 $('*' kaarak.baahar ('aim. pee. aaee.')
 / '/' kaarak.baahar ('dive'));
kaarak = (.ids.baahar ('ld' *) 
 /.number.baahar ('ell. dee. ell.' *)
 / '(' expir ')') 
 ('^' kaarak.baahar ('xpn'/.khaali);
oopar diye gaye mein.ids aur.sankhya antarnihit tokan pahchankarta hain. * mein.out code utpaadan antim maanyata praapt tokan kaa sandarbh detaa haye. ack sankhya koo pahchaanane parr.number.out ('ell. dee. ell.' *) sankhya key baad aaney vaale bhaar shaabdik nirdesh kaa output detaa haye. ack abhivyaktih
utpann karegaah
 ell. dee. ell. 3
 ell. dee. aeye.
 ell. dee. ell. 2
 aiks. pee. aine.
 aim. pee. aaee.
 ell. dee. ell. 5
 jodein
 ell. dee. bee.
 dive
metaa II ack metacompilar kaa pahala pralekhit sanskaran haye, kyonki yeh ack aabhaasi machine key shuruati udaharanon mein seey ack key liye machine code mein sankalit kartaa haye.
kagaj apane aap mein ack adbhut ratna haye jisamen kaee utkrisht udaaharan shamil hain, jisamen metaa II kii bootstrapping bhee shamil haye (yeh sub ack 8k (chhah bitt bite) 1401 parr kiya gayaa thaa!)."-alaan key
mool pepper swatantra roop seey upalabdh naheen haye, lekin doctor dobb kii patrika (aprail 1980) mein punarmudran kiya gayaa thaa. pratilekhit srot code koo vibhinn samay parr upalabdh karaaya gayaa haye (sambhavatah see. pee./aim. upayogkarta samooh dwara). pepper mein metaa II key vivaran kii ack soochi shamil thee, ise saiddhaantik roop seey aabhaasi machine opcode mein ack vyakhyatmak prograam dene key liye manual roop seey sansaadhit kiya jaa sakata thaa; yadi yeh chalaa aur samaan output kaa utpaadan kiya tou karyanvayan sahee thaa.
metaa II mool roop seey avadharana kaa pramaan thaa. ack aadhar jahan seey kaam karna haye.
metaa II koo ack "maanak bhasha" key roop mein prastut naheen kiya gayaa haye, balki ack aise bindu key roop mein prastut kiya gayaa haye jahan seey ack upayogkarta apani "metaa" bhasha vikasit curr sakata haye.
isake baad kaee metaa "bhaashaaen" aaeen. score system development corporation key liye kaam karane gaye jahan way compiler (see. doubleu. aaee. see.) pariyojana key lekhan aur karyanvayan key liye compiler key sadasya they. see. doubleu. aaee. see. kii vakyavinyas bhasha metaa II parr nirmit haye, jisamen ack backtrack vaikalpik operator sakaratmak aur nakaratmak roop seey aage dekhane vaale operator aur kramaadeshit tokan sameekaran shamil hain. cocksey _ 3 aur cocksey _ 4 operations koo hataa diyaa gayaa aur cocksey _ 5 aur cocksey _ 6 koo jodkar sanchaalan koo badalane vaale stack koo jodaa gayaa. lisp 2 parr adharit generator bhasha vaakya rachana parcing bhasha dwara utpaadit pedon koo sansaadhit karati haye. code utpann karane key liye ack generator function key liye ack coll koo vaakya rachana sameekaran mein rakhaa gayaa thaa. inn bhaashaon koo ell key sadasyon dwara vikasit kiya gayaa thaa.aeye. vakyavinyas nirdeshit sanklakon parr aeye. see. aim. sigplan upa-samooh. yeh ullekhaniya haye kii score ney metaa II bhasha key baare mein kaise sochaah
badey aksharon mein "metaa" key saath "metaa" bhasha "shabd kaa upayog kissy bhee sankalak-lekhan" bhasha "koo iss tarah vikasit karane key liye kiya jaataa haye.
score metaa II koo ack aadhar key roop mein samajhaate hain jisase anya metaa "bhaashaon" koo vikasit kiya jaa sakata haye.

