index.js

   1 let express = require('express')
   2 let acorn = require('acorn')
   3 let fs = require('fs')
   4 // let fs = require('node:fs/promises');
   5
   6 let visitor = require('./visitor.js')
   7 let dir = '../wiki-client/lib'
   8 let mods = []
   9
  10 const app = express()
  11
  12
  13 // P A G E S
  14
  15 app.get('/index', async (req,res,next) => {
  16   console.log(new Date().toLocaleTimeString(), 'index')
  17   const reductions = counter()
  18   fs.readdir(dir, async (err, files) => {
  19     mods = await Promise.all(files.map(load))
  20     const doit = branch => {reductions.count(branch.type)}
  21     visitor.wander(mods,doit)
  22     const result = `
  23       <p>${reductions.size()} non-terminals
  24       <br>${reductions.total()} reductions
  25       <p>${reductions.tally()
  26         .map(([k,v]) => `${v} ${link(k)}`)
  27         .join("<br>")}`
  28     res.send(result);
  29     next()
  30   })
  31 })
  32
  33 async function load(file) {
  34   return new Promise(resolve => {
  35     fs.readFile(`${dir}/${file}`, "utf8", (err,text) => {
  36       const tree = acorn.parse(text, {ecmaVersion: "latest"})
  37       resolve({file,text,tree})
  38     })
  39   })
  40 }
  41
  42 function link(key) {
  43   if(key.match(/^Ident/)) return `<a href="/terminal?type=${key}&field=name">${key}</a>`
  44   if(key.match(/^(As|B|L|U).*Ex/)) return `<a href="/terminal?type=${key}&field=operator">${key}</a>`
  45   if(key.match(/^Lit/)) return `<a href="/terminal?type=${key}&field=value">${key}</a>`
  46   return key
  47 }
  48
  49
  50 app.get('/terminal', (req,res) => {
  51   const lits = counter()
  52   const id = req.query.type
  53   const field = req.query.field
  54   const doit = branch => {if(branch.type==id) lits.count(branch[field])}
  55   visitor.wander(mods,doit)
  56   const result = `
  57     <p>${lits.size()} uniques
  58     <br>${lits.total()} total
  59     <p>${lits.tally()
  60       .map(([k,v]) => `${v} <a href="/usage?type=${id}&field=${field}&key=${encodeURIComponent(k)}">${escape(k)}</a>`)
  61       .join("<br>")}`
  62   res.send(result)
  63 })
  64
  65 app.get('/usage', (req,res) => {
  66   const type = req.query.type
  67   const field = req.query.field
  68   const key = req.query.key
  69   const list = []
  70   const doit = (branch,stack) => {
  71     if(branch.type==type && branch[field]==key)
  72       list.push(`${stack.at(-1)} ${sxpr(stack[2],3)}`
  73         // `${stack.length}
  74         // ${stack.at(-1)}-${branch.start}-${branch.end}
  75         // (${stack.slice(0,6).map(n => n.end-n.start).join(" ")})`
  76         )
  77   }
  78   visitor.wander(mods,doit)
  79   res.send(`<pre>${JSON.stringify(req.query,null,2)}</pre>${list.join("<br>")}`)
  80 })
  81
  82
  83 // H E L P E R S
  84
  85 function counter() {
  86   const counts = new Map()
  87   return {
  88     count(item) {
  89       if(counts.has(item))
  90         counts.set(item, counts.get(item)+1)
  91       else
  92         counts.set(item,1)
  93     },
  94     size() {
  95       return counts.size
  96     },
  97     total() {
  98       return [...counts]
  99         .reduce((sum,each) => sum + each[1], 0)
 100     },
 101     tally() {
 102       return [...counts]
 103         .sort((a,b) => a[1]==b[1] ? (a[0]>b[0] ? 1 : -1) : b[1]-a[1])
 104     },
 105   }
 106 }
 107
 108 function escape(text) {
 109   try {
 110     return text
 111       .replace(/&/g, '&amp;')
 112       .replace(/</g, '&lt;')
 113       .replace(/>/g, '&gt;')
 114       .replace(/\*(.+?)\*/g, '<i>$1</i>')
 115   } catch (e) {
 116     return text
 117   }
 118 }
 119
 120 function sxpr(obj,deep,key,child) {
 121   const hilite = obj===child ? 'class="hi"' : ''
 122   const link = word => obj.type == 'Identifier' ? `<a href=/context?id=${word}>${word}</a>` : word
 123   if (obj) {
 124     if(deep) {
 125       const fields = Object.entries(obj)
 126         .filter(([k,v]) => !['start','end','raw','computed','optional','kind'].includes(k))
 127         .map(([k,v]) =>
 128           k=='type' ? abv(v) :
 129           (typeof v == 'string') ? link(expand(v)) :
 130           Array.isArray(v) ? `[${v.map(o => sxpr(o,deep-1,k,child)).join(" ")}]` :
 131           sxpr(v, deep-1, k, child))
 132         .join(" ")
 133       return key ? `<span ${hilite} title=${key}>(${(fields)})</span>` : `(${(fields)})`
 134     } else return elipsis(obj)
 135   } else return `<span title=${obj}>.</span>`
 136 }
 137
 138 function abv(type) {
 139   return `<span title=${type}>${type.replaceAll(/[a-z]/g,'')}</span>`
 140 }
 141
 142 function omit(k,v) {
 143   return k=='type'?v:k=='start'||k=='end'?undefined:v
 144 }
 145
 146 function elipsis(obj) {
 147   const bytes = (obj.end||0)-(obj.start||0)
 148   const dots = '..' + '.'.repeat(Math.floor(Math.log2(bytes||1)))
 149   return `(<span title="${bytes} bytes">${dots}</span>)`
 150 }
 151
 152 function expand(text) {
 153   return text
 154     .replace(/&/g, '&amp;')
 155     .replace(/</g, '&lt;')
 156     .replace(/>/g, '&gt;')
 157     .replace(/\*(.+?)\*/g, '<i>$1</i>')
 158 };
 159
 160 app.listen(1954)