读取

Reads input from the active input stream.

Syntax: 读取 [行]

Category#

io

Related#

• 行
• 写入

Examples#

radix/corpus/lege/lege.fab (canonical · keyword)#

Reads input from the active input stream.

# =============================================================================
# 读取 — Reads input from the active input stream.
# =============================================================================
#
# What this teaches:
#   • stdin input with `读取` — reads one line from the active input stream
#   • the `↦ regex` 变换 — compiling a 文本 pattern into a regex value
#
# Common mistakes:
#   • Not checking is null before using the value — read may return null at end of input.
#
# See also: 行, 写入
# =============================================================================

# 读取 and regex 转换 — I/O read and compiled pattern expressions
#
# 常量 _ pattern ← "\d+" ↦ regex   -- compiled regex from 文本
# 常量 _ input ← 读取                  -- stdin line read
#
# GRAMMAR:
#   转换 :← stringLit '↦' 'regex'
#   readExpr :← '读取'
#
# EXPECTED OUTPUT:
#   Regex pattern diagnostic, then one stdin line (no .expected — interactive).
#
# BACKEND: Rust/Go/roundtrip e2e whitelist — 读取 not yet lowered for Rust/Go
# (whitelist: 读取/lege.fab).

main {
    const regex pattern ← "(?i)\d+" ↦ regex
    print pattern
    const string ∪ none input ← read
    print input
}