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// Process *this* and _that_
//
// Insert each marker as a separate text token, and add it to delimiter list
//
function emphasis_tokenize (state, silent) {
const start = state.pos
const marker = state.src.charCodeAt(start)
if (silent) { return false }
if (marker !== 0x5F /* _ */ && marker !== 0x2A /* * */) { return false }
const scanned = state.scanDelims(state.pos, marker === 0x2A)
for (let i = 0; i < scanned.length; i++) {
const token = state.push('text', '', 0)
token.content = String.fromCharCode(marker)
state.delimiters.push({
// Char code of the starting marker (number).
//
marker,
// Total length of these series of delimiters.
//
length: scanned.length,
// A position of the token this delimiter corresponds to.
//
token: state.tokens.length - 1,
// If this delimiter is matched as a valid opener, `end` will be
// equal to its position, otherwise it's `-1`.
//
end: -1,
// Boolean flags that determine if this delimiter could open or close
// an emphasis.
//
open: scanned.can_open,
close: scanned.can_close
})
}
state.pos += scanned.length
return true
}
function postProcess (state, delimiters) {
const max = delimiters.length
for (let i = max - 1; i >= 0; i--) {
const startDelim = delimiters[i]
if (startDelim.marker !== 0x5F/* _ */ && startDelim.marker !== 0x2A/* * */) {
continue
}
// Process only opening markers
if (startDelim.end === -1) {
continue
}
const endDelim = delimiters[startDelim.end]
// If the previous delimiter has the same marker and is adjacent to this one,
// merge those into one strong delimiter.
//
// `<em><em>whatever</em></em>` -> `<strong>whatever</strong>`
//
const isStrong = i > 0 &&
delimiters[i - 1].end === startDelim.end + 1 &&
// check that first two markers match and adjacent
delimiters[i - 1].marker === startDelim.marker &&
delimiters[i - 1].token === startDelim.token - 1 &&
// check that last two markers are adjacent (we can safely assume they match)
delimiters[startDelim.end + 1].token === endDelim.token + 1
const ch = String.fromCharCode(startDelim.marker)
const token_o = state.tokens[startDelim.token]
token_o.type = isStrong ? 'strong_open' : 'em_open'
token_o.tag = isStrong ? 'strong' : 'em'
token_o.nesting = 1
token_o.markup = isStrong ? ch + ch : ch
token_o.content = ''
const token_c = state.tokens[endDelim.token]
token_c.type = isStrong ? 'strong_close' : 'em_close'
token_c.tag = isStrong ? 'strong' : 'em'
token_c.nesting = -1
token_c.markup = isStrong ? ch + ch : ch
token_c.content = ''
if (isStrong) {
state.tokens[delimiters[i - 1].token].content = ''
state.tokens[delimiters[startDelim.end + 1].token].content = ''
i--
}
}
}
// Walk through delimiter list and replace text tokens with tags
//
function emphasis_post_process (state) {
const tokens_meta = state.tokens_meta
const max = state.tokens_meta.length
postProcess(state, state.delimiters)
for (let curr = 0; curr < max; curr++) {
if (tokens_meta[curr] && tokens_meta[curr].delimiters) {
postProcess(state, tokens_meta[curr].delimiters)
}
}
}
export default {
tokenize: emphasis_tokenize,
postProcess: emphasis_post_process
}
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