ai-content-maker/.venv/Lib/site-packages/torch/include/ATen/code_template.h

244 lines
6.7 KiB
C++

#pragma once
#include <c10/util/irange.h>
#include <sstream>
#include <string>
#include <unordered_map>
#include <vector>
namespace at::jit {
// A template environment is a mapping from template variable names, e.g.,
// identifier (corresponding to $identifier) to their expansions.
//
// This template environment supports storing strings, numbers and lists
// of strings, and can be chained together (so that lookup proceeds in
// in the top level environment, and then recurses into a parent
// environment if the key is not found.)
struct TemplateEnv {
TemplateEnv() = default;
TemplateEnv(TemplateEnv& parent) : parent(&parent) {}
using string_list = std::vector<std::string>;
// Add a string 'v' to the map at key 'k'.
void s(const std::string& k, const std::string& v) {
strings_[k] = v;
lists_.erase(k);
}
// Add a number 'v' to the map at key 'k'
template <typename T>
void d(const std::string& k, const T& v) {
strings_[k] = c10::to_string(v);
lists_.erase(k);
}
// Retrieve the string representation of the value stored at 'k' from the map.
// Raises an exception if the key is not found.
const std::string& s(const std::string& k) const {
if (strings_.count(k) == 0) {
if (parent) {
return parent->s(k);
}
notFound(k);
}
return strings_.at(k);
}
// Store a list of strings 'v' in the map at 'k'.
void v(const std::string& k, const string_list& v) {
lists_[k] = v;
strings_.erase(k);
}
// Retrieve a list of strings stored at 'k' from the map.
// Raises an exception if the key is not found.
const string_list& v(const std::string& k) const {
if (lists_.count(k) == 0) {
if (parent) {
return parent->v(k);
}
notFound(k);
}
return lists_.at(k);
}
// Test if a string 'k' is a string (as opposed to a list.)
bool keyIsString(const std::string& k) const {
if (strings_.count(k) > 0)
return true;
if (lists_.count(k) > 0)
return false;
if (parent)
return parent->keyIsString(k);
notFound(k);
}
private:
[[noreturn]] void notFound(const std::string& k) const {
std::stringstream ss;
ss << "key not found: " << k;
throw std::logic_error(ss.str());
}
std::unordered_map<std::string, std::string> strings_;
std::unordered_map<std::string, string_list> lists_;
TemplateEnv* parent{nullptr};
};
/*
# Match $identifier or ${identifier} and replace with the value in env.
# If this identifier is at the beginning of whitespace on a line
# and its value is a list then it is treated as
# block substitution by indenting all lines of all elements.
# If the identifier is on a line starting with non-whitespace and a list
# then it is comma separated. ${,foo} will insert a comma before the list
# if this list is not empty and ${foo,} will insert one after.
*/
struct CodeTemplate {
/* implicit */ CodeTemplate(std::string t) : template_text(std::move(t)) {}
std::string format(const TemplateEnv& env) const {
std::stringstream out;
size_t pos = 0;
size_t indent = 0;
bool all_whitespace = true;
while (pos < template_text.size()) {
char c = template_text[pos];
if (c == '$') {
std::stringstream kss;
// NOLINTNEXTLINE(cppcoreguidelines-init-variables)
bool comma_before;
// NOLINTNEXTLINE(cppcoreguidelines-init-variables)
bool comma_after;
size_t new_pos = parseKey(pos, kss, comma_before, comma_after);
std::string k = kss.str();
bool is_string = env.keyIsString(k);
if (all_whitespace) {
if (is_string)
emitStringWithIndents(out, indent, env.s(k));
else
emitLinesIndented(out, indent, env.v(k));
} else {
if (is_string)
out << env.s(k);
else
emitCommaSeparatedList(out, env.v(k), comma_before, comma_after);
}
all_whitespace = false;
pos = new_pos;
} else {
out << c;
if (!isspace(c))
all_whitespace = false;
indent++;
if (c == '\n') {
indent = 0;
all_whitespace = true;
}
pos++;
}
}
return out.str();
}
private:
using string_list = std::vector<std::string>;
char charAt(size_t p) const {
if (p >= template_text.size())
throw std::logic_error("EOS found in key");
return template_text[p];
}
size_t parseKey(
size_t pos,
std::ostream& k,
bool& comma_before,
bool& comma_after) const {
comma_before = false;
comma_after = false;
pos++;
if (charAt(pos) == '{') {
pos++;
if (charAt(pos) == ',') {
comma_before = true;
pos++;
}
pos = parseIdent(pos, k);
if (charAt(pos) == ',') {
comma_after = true;
pos++;
}
if (charAt(pos) != '}')
throw std::logic_error("missing terminating '}'");
pos++;
return pos;
} else {
return parseIdent(pos, k);
}
}
size_t parseIdent(size_t pos, std::ostream& k) const {
while (pos < template_text.size() &&
(isalnum(template_text[pos]) || template_text[pos] == '_')) {
k << template_text[pos];
pos++;
}
return pos;
}
void emitCommaSeparatedList(
std::ostream& out,
const string_list& strings,
bool comma_before,
bool comma_after) const {
if (comma_before && !strings.empty())
out << ", ";
for (const auto i : c10::irange(strings.size())) {
if (i > 0)
out << ", ";
out << strings[i];
}
if (comma_after && !strings.empty())
out << ", ";
}
// These indentation functions follow the convention that they never emit
// leading or trailing newlines when the input string does not have leading
// or trailing newlines. It's the responsibility of the calling function
// to indent correctly in the context.
void emitIndent(std::ostream& out, size_t indent) const {
for (C10_UNUSED const auto i : c10::irange(indent)) {
out << " ";
}
}
void emitStringWithIndents(
std::ostream& out,
size_t indent,
const std::string& str) const {
for (auto c : str) {
out << c;
if (c == '\n') {
emitIndent(out, indent);
}
}
}
void emitLinesIndented(
std::stringstream& out,
size_t indent,
const string_list& strings) const {
for (const auto i : c10::irange(strings.size())) {
if (i > 0)
emitIndent(out, indent);
emitStringWithIndents(out, indent, strings[i]);
if (i + 1 != strings.size())
out << "\n";
}
}
std::string template_text;
};
static inline std::string format(const std::string& fmt, TemplateEnv& env) {
return CodeTemplate(fmt).format(env);
}
} // namespace at::jit